cloudflare Vulnerabilities

A cache poisoning vulnerability has been found in the Pingora HTTP proxy framework’s default cache key construction. The issue occurs because the default HTTP cache key implementation generates cache keys using only the URI path, excluding critical factors such as the host header (authority). Operators relying on the default are vulnerable to cache poisoning, and cross-origin responses may be improperly served to users. Impact This vulnerability affects users of Pingora's alpha proxy caching feature who relied on the default CacheKey implementation. An attacker could exploit this for: * Cross-tenant data leakage: In multi-tenant deployments, poison the cache so that users from one tenant receive cached responses from another tenant * Cache poisoning attacks: Serve malicious content to legitimate users by poisoning shared cache entries Cloudflare's CDN infrastructure was not affected by this vulnerability, as Cloudflare's default cache key implementation uses multiple factors to prevent cache key poisoning and never made use of the previously provided default. Mitigation: We strongly recommend Pingora users to upgrade to Pingora v0.8.0 or higher, which removes the insecure default cache key implementation. Users must now explicitly implement their own callback that includes appropriate factors such as Host header, origin server HTTP scheme, and other attributes their cache should vary on. Pingora users on previous versions may also remove any of their default CacheKey usage and implement their own that should at minimum include the host header / authority and upstream peer’s HTTP scheme.

An HTTP Request Smuggling vulnerability (CWE-444) has been found in Pingora's parsing of HTTP/1.0 and Transfer-Encoding requests. The issue occurs due to improperly allowing HTTP/1.0 request bodies to be close-delimited and incorrect handling of multiple Transfer-Encoding values, allowing attackers to send HTTP/1.0 requests in a way that would desync Pingora’s request framing from backend servers’. Impact This vulnerability primarily affects standalone Pingora deployments in front of certain backends that accept HTTP/1.0 requests. An attacker could craft a malicious payload following this request that Pingora forwards to the backend in order to: * Bypass proxy-level ACL controls and WAF logic * Poison caches and upstream connections, causing subsequent requests from legitimate users to receive responses intended for smuggled requests * Perform cross-user attacks by hijacking sessions or smuggling requests that appear to originate from the trusted proxy IP Cloudflare's CDN infrastructure was not affected by this vulnerability, as its ingress proxy layers forwarded HTTP/1.1 requests only, rejected ambiguous framing such as invalid Content-Length values, and forwarded a single Transfer-Encoding: chunked header for chunked requests. Mitigation: Pingora users should upgrade to Pingora v0.8.0 or higher that fixes this issue by correctly parsing message length headers per RFC 9112 and strictly adhering to more RFC guidelines, including that HTTP request bodies are never close-delimited. As a workaround, users can reject certain requests with an error in the request filter logic in order to stop processing bytes on the connection and disable downstream connection reuse. The user should reject any non-HTTP/1.1 request, or a request that has invalid Content-Length, multiple Transfer-Encoding headers, or Transfer-Encoding header that is not an exact “chunked” string match.

An HTTP request smuggling vulnerability (CWE-444) was found in Pingora's handling of HTTP/1.1 connection upgrades. The issue occurs when a Pingora proxy reads a request containing an Upgrade header, causing the proxy to pass through the rest of the bytes on the connection to a backend before the backend has accepted the upgrade. An attacker can thus directly forward a malicious payload after a request with an Upgrade header to that backend in a way that may be interpreted as a subsequent request header, bypassing proxy-level security controls and enabling cross-user session hijacking. Impact This vulnerability primarily affects standalone Pingora deployments where a Pingora proxy is exposed to external traffic. An attacker could exploit this to: * Bypass proxy-level ACL controls and WAF logic * Poison caches and upstream connections, causing subsequent requests from legitimate users to receive responses intended for smuggled requests * Perform cross-user attacks by hijacking sessions or smuggling requests that appear to originate from the trusted proxy IP Cloudflare's CDN infrastructure was not affected by this vulnerability, as ingress proxies in the CDN stack maintain proper HTTP parsing boundaries and do not prematurely switch to upgraded connection forwarding mode. Mitigation: Pingora users should upgrade to Pingora v0.8.0 or higher As a workaround, users may return an error on requests with the Upgrade header present in their request filter logic in order to stop processing bytes beyond the request header and disable downstream connection reuse.

The CombinedMult function in the CIRCL ecc/p384 package (secp384r1 curve) produces an incorrect value for specific inputs. The issue is fixed by using complete addition formulas. ECDH and ECDSA signing relying on this curve are not affected. The bug was fixed in v1.6.3 https://github.com/cloudflare/circl/releases/tag/v1.6.3 .

SummaryA command injection vulnerability (CWE-78) has been found to exist in the `wrangler pages deploy` command. The issue occurs because the `--commit-hash` parameter is passed directly to a shell command without proper validation or sanitization, allowing an attacker with control of `--commit-hash` to execute arbitrary commands on the system running Wrangler. Root causeThe commitHash variable, derived from user input via the --commit-hash CLI argument, is interpolated directly into a shell command using template literals (e.g.,  execSync(`git show -s --format=%B ${commitHash}`)). Shell metacharacters are interpreted by the shell, enabling command execution. ImpactThis vulnerability is generally hard to exploit, as it requires --commit-hash to be attacker controlled. The vulnerability primarily affects CI/CD environments where `wrangler pages deploy` is used in automated pipelines and the --commit-hash parameter is populated from external, potentially untrusted sources. An attacker could exploit this to: * Run any shell command. * Exfiltrate environment variables. * Compromise the CI runner to install backdoors or modify build artifacts. Credits Disclosed responsibly by kny4hacker. Mitigation * Wrangler v4 users are requested to upgrade to Wrangler v4.59.1 or higher. * Wrangler v3 users are requested to upgrade to Wrangler v3.114.17 or higher. * Users on Wrangler v2 (EOL) should upgrade to a supported major version.

In gokey versions <0.2.0, a flaw in the seed decryption logic resulted in passwords incorrectly being derived solely from the initial vector and the AES-GCM authentication tag of the key seed. This issue has been fixed in gokey version 0.2.0. This is a breaking change. The fix has invalidated any passwords/secrets that were derived from the seed file (using the -s option). Even if the input seed file stays the same, version 0.2.0 gokey will generate different secrets. Impact This vulnerability impacts generated keys/secrets using a seed file as an entropy input (using the -s option). Keys/secrets generated just from the master password (without the -s option) are not impacted. The confidentiality of the seed itself is also not impacted (it is not required to regenerate the seed itself). Specific impact includes: * keys/secrets generated from a seed file may have lower entropy: it was expected that the whole seed would be used to generate keys (240 bytes of entropy input), where in vulnerable versions only 28 bytes was used * a malicious entity could have recovered all passwords, generated from a particular seed, having only the seed file in possession without the knowledge of the seed master password Patches The code logic bug has been fixed in gokey version 0.2.0 and above. Due to the deterministic nature of gokey, fixed versions will produce different passwords/secrets using seed files, as all seed entropy will be used now. System secret rotation guidance It is advised for users to regenerate passwords/secrets using the patched version of gokey (0.2.0 and above), and provision/rotate these secrets into respective systems in place of the old secret. A specific rotation procedure is system-dependent, but most common patterns are described below. Systems that do not require the old password/secret for rotation Such systems usually have a "Forgot password" facility or a similar facility allowing users to rotate their password/secrets by sending a unique "magic" link to the user's email or phone. In such cases users are advised to use this facility and input the newly generated password secret, when prompted by the system. Systems that require the old password/secret for rotation Such systems usually have a modal password rotation window usually in the user settings section requiring the user to input the old and the new password sometimes with a confirmation. To generate/recover the old password in such cases users are advised to: * temporarily download gokey version 0.1.3 https://github.com/cloudflare/gokey/releases/tag/v0.1.3 for their respective operating system to recover the old password * use gokey version 0.2.0 or above to generate the new password * populate the system provided password rotation form Systems that allow multiple credentials for the same account to be provisioned Such systems usually require a secret or a cryptographic key as a credential for access, but allow several credentials at the same time. One example is SSH: a particular user may have several authorized public keys configured on the SSH server for access. For such systems users are advised to: * generate a new secret/key/credential using gokey version 0.2.0 or above * provision the new secret/key/credential in addition to the existing credential on the system * verify that the access or required system operation is still possible with the new secret/key/credential * revoke authorization for the existing/old credential from the system Credit This vulnerability was found by Théo Cusnir ( @mister_mime https://hackerone.com/mister_mime ) and responsibly disclosed through Cloudflare's bug bounty program.

Cloudflare quiche was discovered to be vulnerable to an infinite loop when sending packets containing RETIRE_CONNECTION_ID frames. QUIC connections possess a set of connection identifiers (IDs); see Section 5.1 of RFC 9000 https://datatracker.ietf.org/doc/html/rfc9000#section-5.1 . Once the QUIC handshake completes, a local endpoint is responsible for issuing and retiring Connection IDs that are used by the remote peer to populate the Destination Connection ID field in packets sent from remote to local. Each Connection ID has a sequence number to ensure synchronization between peers. An unauthenticated remote attacker can exploit this vulnerability by first completing a handshake and then sending a specially-crafted set of frames that trigger a connection ID retirement in the victim. When the victim attempts to send a packet containing RETIRE_CONNECTION_ID frames, Section 19.16 of RFC 9000 https://datatracker.ietf.org/doc/html/rfc9000#section-19.6 requires that the sequence number of the retired connection ID must not be the same as the sequence number of the connection ID used by the packet. In other words, a packet cannot contain a frame that retires itself. In scenarios such as path migration, it is possible for there to be multiple active paths with different active connection IDs that could be used to retire each other. The exploit triggered an unintentional behaviour of a quiche design feature that supports retirement across paths while maintaining full connection ID synchronization, leading to an infinite loop.This issue affects quiche: from 0.15.0 before 0.24.5.

Impact Cloudflare quiche was discovered to be vulnerable to incorrect congestion window growth, which could cause it to send data at a rate faster than the path might actually support. An unauthenticated remote attacker can exploit the vulnerability by first completing a handshake and initiating a congestion-controlled data transfer towards itself. Then, it could manipulate the victim's congestion control state by sending ACK frames covering a large range of packet numbers (including packet numbers that had never been sent); see RFC 9000 Section 19.3. The victim could grow the congestion window beyond typical expectations and allow more bytes in flight than the path might really support. In extreme cases, the window might grow beyond the limit of the internal variable's type, leading to an overflow panic. Patches quiche 0.24.4 is the earliest version containing the fix for this issue.

Impact Cloudflare quiche was discovered to be vulnerable to incorrect congestion window growth, which could cause it to send data at a rate faster than the path might actually support. An unauthenticated remote attacker can exploit the vulnerability by first completing a handshake and initiating a congestion-controlled data transfer towards itself. Then, it could manipulate the victim's congestion control state by sending ACK frames exercising an opportunistic ACK attack; see RFC 9000 Section 21.4. The victim could grow the congestion window beyond typical expectations and allow more bytes in flight than the path might really support. Patches quiche 0.24.4 is the earliest version containing the fix for this issue.

A Server-Side Request Forgery (SSRF) vulnerability was identified in the @opennextjs/cloudflare package. The vulnerability stems from an unimplemented feature in the Cloudflare adapter for Open Next, which allowed unauthenticated users to proxy arbitrary remote content via the /_next/image endpoint. This issue allowed attackers to load remote resources from arbitrary hosts under the victim site’s domain for any site deployed using the Cloudflare adapter for Open Next.  For example: https://victim-site.com/_next/image?url=https://attacker.com In this example, attacker-controlled content from attacker.com is served through the victim site’s domain (victim-site.com), violating the same-origin policy and potentially misleading users or other services. Impact: * SSRF via unrestricted remote URL loading * Arbitrary remote content loading * Potential internal service exposure or phishing risks through domain abuse Mitigation: The following mitigations have been put in place: * Server side updates to Cloudflare’s platform to restrict the content loaded via the /_next/image endpoint to images. The update automatically mitigates the issue for all existing and any future sites deployed to Cloudflare using the affected version of the Cloudflare adapter for Open Next * Root cause fix https://github.com/opennextjs/opennextjs-cloudflare/pull/727  to the Cloudflare adapter for Open Next. The patched version of the adapter is found here  @opennextjs/cloudflare@1.3.0 https://www.npmjs.com/package/@opennextjs/cloudflare/v/1.3.0 * Package dependency update https://github.com/cloudflare/workers-sdk/pull/9608  to create-cloudflare (c3) to use the fixed version of the Cloudflare adapter for Open Next. The patched version of create-cloudflare is found here:  create-cloudflare@2.49.3 https://www.npmjs.com/package/create-cloudflare/v/2.49.3 In addition to the automatic mitigation deployed on Cloudflare’s platform, we encourage affected users to upgrade to @opennext/cloudflare v1.3.0 and use the remotePatterns https://nextjs.org/docs/pages/api-reference/components/image#remotepatterns filter in Next config https://nextjs.org/docs/pages/api-reference/components/image#remotepatterns if they need to allow-list external urls with images assets.

A request smuggling vulnerability identified within Pingora’s proxying framework, pingora-proxy, allows malicious HTTP requests to be injected via manipulated request bodies on cache HITs, leading to unauthorized request execution and potential cache poisoning. Fixed in:  https://github.com/cloudflare/pingora/commit/fda3317ec822678564d641e7cf1c9b77ee3759ff https://github.com/cloudflare/pingora/commit/fda3317ec822678564d641e7cf1c9b77ee3759ff Impact: The issue could lead to request smuggling in cases where Pingora’s proxying framework, pingora-proxy, is used for caching allowing an attacker to manipulate headers and URLs in subsequent requests made on the same HTTP/1.1 connection.

PKCE was implemented in the OAuth implementation in workers-oauth-provider that is part of MCP framework https://github.com/cloudflare/workers-mcp . However, it was found that an attacker could cause the check to be skipped. Fixed in: https://github.com/cloudflare/workers-oauth-provider/pull/27 https://github.com/cloudflare/workers-oauth-provider/pull/27 Impact: PKCE is a defense-in-depth mechanism against certain kinds of attacks and was an optional extension in OAuth 2.0 which became required in the OAuth 2.1 draft. (Note that the MCP specification requires OAuth 2.1.). This bug completely bypasses PKCE protection.

The OAuth implementation in workers-oauth-provider that is part of MCP framework https://github.com/cloudflare/workers-mcp , did not correctly validate that redirect_uri was on the allowed list of redirect URIs for the given client registration. Fixed in:  https://github.com/cloudflare/workers-oauth-provider/pull/26 https://github.com/cloudflare/workers-oauth-provider/pull/26 Impact: Under certain circumstances (see below), if a victim had previously authorized with a server built on workers-oath-provider, and an attacker could later trick the victim into visiting a malicious web site, then attacker could potentially steal the victim's credentials to the same OAuth server and subsequently impersonate them. In order for the attack to be possible, the OAuth server's authorized callback must be designed to auto-approve authorizations that appear to come from an OAuth client that the victim has authorized previously. The authorization flow is not implemented by workers-oauth-provider; it is up to the application built on top to decide whether to implement such automatic re-authorization. However, many applications do implement such logic. Note: It is a basic, well-known requirement that OAuth servers should verify that the redirect URI is among the allowed list for the client, both during the authorization flow and subsequently when exchanging the authorization code for an access token. workers-oauth-provider implemented only the latter check, not the former. Unfortunately, the former is the much more important check. Readers who are familiar with OAuth may recognize that failing to check redirect URIs against the allowed list is a well-known, basic mistake, covered extensively in the RFC and elsewhere. The author of this library would like everyone to know that he was, in fact, well-aware of this requirement, thought about it a lot while designing the library, and then, somehow, forgot to actually make sure the check was in the code. That is, it's not that he didn't know what he was doing, it's that he knew what he was doing but flubbed it.

When copying files with rsync, octorpki uses the "-a" flag 0, which forces rsync to copy binaries with the suid bit set as root. Since the provided service definition defaults to root ( https://github.com/cloudflare/cfrpki/blob/master/package/octorpki.service ) this could allow for a vector, when combined with another vulnerability that causes octorpki to process a malicious TAL file, for a local privilege escalation.

Improper Privilege Management vulnerability in Cloudflare WARP on Windows allows File Manipulation. User with a low system privileges  can create a set of symlinks inside the C:\ProgramData\Cloudflare\warp-diag-partials folder. After triggering the 'Reset all settings" option the WARP service will delete the files that the symlink was pointing to. Given the WARP service operates with System privileges this might lead to deleting files owned by the System user. This issue affects WARP: before 2024.12.492.0.

Cloudflare Quiche (through version 0.19.1/0.20.0) was affected by an unlimited resource allocation vulnerability causing rapid increase of memory usage of the system running quiche server or client. A remote attacker could take advantage of this vulnerability by repeatedly sending an unlimited number of 1-RTT CRYPTO frames after previously completing the QUIC handshake. Exploitation was possible for the duration of the connection which could be extended by the attacker.  quiche 0.19.2 and 0.20.1 are the earliest versions containing the fix for this issue.

Cloudflare quiche was discovered to be vulnerable to unbounded storage of information related to connection ID retirement, which could lead to excessive resource consumption. Each QUIC connection possesses a set of connection Identifiers (IDs); see RFC 9000 Section 5.1 https://datatracker.ietf.org/doc/html/rfc9000#section-5.1 . Endpoints declare the number of active connection IDs they are willing to support using the active_connection_id_limit transport parameter. The peer can create new IDs using a NEW_CONNECTION_ID frame but must stay within the active ID limit. This is done by retirement of old IDs, the endpoint sends NEW_CONNECTION_ID includes a value in the retire_prior_to field, which elicits a RETIRE_CONNECTION_ID frame as confirmation. An unauthenticated remote attacker can exploit the vulnerability by sending NEW_CONNECTION_ID frames and manipulating the connection (e.g. by restricting the peer's congestion window size) so that RETIRE_CONNECTION_ID frames can only be sent at a slower rate than they are received, leading to storage of information related to connection IDs in an unbounded queue. Quiche versions 0.19.2 and 0.20.1 are the earliest to address this problem. There is no workaround for affected versions.

The Cloudflare Wordpress plugin was found to be vulnerable to improper authentication. The vulnerability enables attackers with a lower privileged account to access data from the Cloudflare API.

Cloudflare version of zlib library was found to be vulnerable to memory corruption issues affecting the deflation algorithm implementation (deflate.c). The issues resulted from improper input validation and heap-based buffer overflow. A local attacker could exploit the problem during compression using a crafted malicious file potentially leading to denial of service of the software. Patches: The issue has been patched in commit 8352d10 https://github.com/cloudflare/zlib/commit/8352d108c05db1bdc5ac3bdf834dad641694c13c . The upstream repository is not affected.

The V8 inspector intentionally allows arbitrary code execution within the Workers sandbox for debugging. wrangler dev would previously start an inspector server listening on all network interfaces. This would allow an attacker on the local network to connect to the inspector and run arbitrary code. Additionally, the inspector server did not validate Origin/Host headers, granting an attacker that can trick any user on the local network into opening a malicious website the ability to run code. If wrangler dev --remote was being used, an attacker could access production resources if they were bound to the worker. This issue was fixed in wrangler@3.19.0 and wrangler@2.20.2. Whilst wrangler dev's inspector server listens on local interfaces by default as of wrangler@3.16.0, an SSRF vulnerability in miniflare https://github.com/cloudflare/workers-sdk/security/advisories/GHSA-fwvg-2739-22v7  (CVE-2023-7078) allowed access from the local network until wrangler@3.18.0. wrangler@3.19.0 and wrangler@2.20.2 introduced validation for the Origin/Host headers.

Sending specially crafted HTTP requests and inspector messages to Wrangler's dev server could result in any file on the user's computer being accessible over the local network. An attacker that could trick any user on the local network into opening a malicious website could also read any file.

Sending specially crafted HTTP requests to Miniflare's server could result in arbitrary HTTP and WebSocket requests being sent from the server. If Miniflare was configured to listen on external network interfaces (as was the default in wrangler until 3.19.0), an attacker on the local network could access other local servers.

quiche v. 0.15.0 through 0.19.0 was discovered to be vulnerable to unbounded queuing of path validation messages, which could lead to excessive resource consumption. QUIC path validation (RFC 9000 Section 8.2) requires that the recipient of a PATH_CHALLENGE frame responds by sending a PATH_RESPONSE. An unauthenticated remote attacker can exploit the vulnerability by sending PATH_CHALLENGE frames and manipulating the connection (e.g. by restricting the peer's congestion window size) so that PATH_RESPONSE frames can only be sent at the slower rate than they are received; leading to storage of path validation data in an unbounded queue. Quiche versions greater than 0.19.0 address this problem.

The tokio-boring library in version 4.0.0 is affected by a memory leak issue that can lead to excessive resource consumption and potential DoS by resource exhaustion. The set_ex_data function used by the library did not deallocate memory used by pre-existing data in memory each time after completing a TLS connection causing the program to consume more resources with each new connection.

Zero Trust Administrators have the ability to disallow end users from disabling WARP on their devices. Override codes can also be created by the Administrators to allow a device to temporarily be disconnected from WARP, however, due to lack of server side validation, an attacker with local access to the device, could extend the maximum allowed disconnected time of WARP client granted by an override code by changing the date & time on the local device where WARP is running.

Due to a misconfiguration, the WARP Mobile Client (< 6.29) for Android was susceptible to a tapjacking attack. In the event that an attacker built a malicious application and managed to install it on a victim's device, the attacker would be able to trick the user into believing that the app shown on the screen was the WARP client when in reality it was the attacker's app.

Due to lack of a security policy, the WARP Mobile Client (<=6.29) for Android was susceptible to this vulnerability which allowed a malicious app installed on a victim's device to exploit a peculiarity in an Android function, wherein under certain conditions, the malicious app could dictate the task behaviour of the WARP app.

lol-html can cause panics on certain HTML inputs. Anyone processing arbitrary 3rd party HTML with the library is affected.

A vulnerability was discovered in the odoh-rs rust crate that stems from faulty logic during the parsing of encrypted queries. This issue specifically occurs when processing encrypted query data received from remote clients and enables an attacker with knowledge of this vulnerability to craft and send specially designed encrypted queries to targeted ODOH servers running with odoh-rs. Upon successful exploitation, the server will crash abruptly, disrupting its normal operation and rendering the service temporarily unavailable.

The Wrangler command line tool  (<=wrangler@3.1.0 or <=wrangler@2.20.1) was affected by a directory traversal vulnerability when running a local development server for Pages (wrangler pages dev command). This vulnerability enabled an attacker in the same network as the victim to connect to the local development server and access the victim's files present outside of the directory for the development server.

The Cloudflare WARP client for Windows assigns loopback IPv4 addresses for the DNS Servers, since WARP acts as local DNS server that performs DNS queries in a secure manner, however, if a user is connected to WARP over an IPv6-capable network, te WARP client did not assign loopback IPv6 addresses but Unique Local Addresses, which under certain conditions could point towards unknown devices in the same local network which enables an Attacker to view DNS queries made by the device.

Cloudflare WARP client for Windows (up to v2023.3.381.0) allowed a malicious actor to remotely access the warp-svc.exe binary due to an insufficient access control policy on an IPC Named Pipe. This would have enabled an attacker to trigger WARP connect and disconnect commands, as well as obtaining network diagnostics and application configuration from the target's device. It is important to note that in order to exploit this, a set of requirements would need to be met, such as the target's device must've been reachable on port 445, allowed authentication with NULL sessions or otherwise having knowledge of the target's credentials.

A debug function in the lua-resty-json package, up to commit id 3ef9492bd3a44d9e51301d6adc3cd1789c8f534a (merged in PR #14) contained an out of bounds access bug that could have allowed an attacker to launch a DoS if the function was used to parse untrusted input data. It is important to note that because this debug function was only used in tests and demos, it was not exploitable in a normal environment.

An unchecked read in NTP server in github.com/cloudflare/cfnts prior to commit 783490b https://github.com/cloudflare/cfnts/commit/783490b913f05e508a492cd7b02e3c4ec2297b71  enabled a remote attacker to trigger a panic by sending an NTSAuthenticator packet with extension length longer than the packet contents.

Prior to version v1.20230419.0, the FormData API implementation was subject to an integer overflow. If a FormData instance contained more than 2^31 elements, the forEach() method could end up reading from the wrong location in memory while iterating over elements. This would most likely lead to a segmentation fault, but could theoretically allow arbitrary undefined behavior. In order for the bug to be exploitable, the process would need to be able to allocate 160GB of RAM. Due to this, the bug was never exploitable on the Cloudflare Workers platform, but could theoretically be exploitable on deployments of workerd running on machines with a huge amount of memory. Moreover, in order to be remotely exploited, an attacker would have to upload a single form-encoded HTTP request of at least tens of gigabytes in size. The application code would then have to use request.formData() to parse the request and formData.forEach() to iterate over this data. Due to these limitations, the exploitation likelihood was considered Low. A fix that addresses this vulnerability has been released in version v1.20230419.0 and users are encouraged to update to the latest version available.

When sampling randomness for a shared secret, the implementation of Kyber and FrodoKEM, did not check whether crypto/rand.Read() returns an error. In rare deployment cases (error thrown by the Read() function), this could lead to a predictable shared secret. The tkn20 and blindrsa components did not check whether enough randomness was returned from the user provided randomness source. Typically the user provides crypto/rand.Reader, which in the vast majority of cases will always return the right number random bytes. In the cases where it does not, or the user provides a source that does not, the blinding for blindrsa is weak and integrity of the plaintext is not ensured in tkn20.

Due to a hardlink created in the ProgramData folder during the repair process of the software, the installer (MSI) of WARP Client for Windows (<= 2022.12.582.0) allowed a malicious attacker to forge the destination of the hardlink and escalate privileges, overwriting SYSTEM protected files. As Cloudflare WARP client for Windows (up to version 2022.5.309.0) allowed creation of mount points from its ProgramData folder, during installation of the WARP client, it was possible to escalate privileges and overwrite SYSTEM protected files.

An unprivileged (non-admin) user can exploit an Improper Access Control vulnerability in the Cloudflare WARP Client for Windows (<= 2022.12.582.0) to perform privileged operations with SYSTEM context by working with a combination of opportunistic locks (oplock) and symbolic links (which can both be created by an unprivileged user). After installing the Cloudflare WARP Client (admin privileges required), an MSI-Installer is placed under C:\Windows\Installer. The vulnerability lies in the repair function of this MSI. ImpactAn unprivileged (non-admin) user can exploit this vulnerability to perform privileged operations with SYSTEM context, including deleting arbitrary files and reading arbitrary file content. This can lead to a variety of attacks, including the manipulation of system files and privilege escalation. PatchesA new installer with a fix that addresses this vulnerability was released in version 2023.3.381.0. While the WARP Client itself is not vulnerable (only the installer), users are encouraged to upgrade to the latest version and delete any older installers present in their systems.

A vulnerability has been discovered in cloudflared's installer (<= 2023.3.0) for Windows 32-bits devices that allows a local attacker with no administrative permissions to escalate their privileges on the affected device. This vulnerability exists because the MSI installer used by cloudflared relied on a world-writable directory. An attacker with local access to the device (without Administrator rights) can use symbolic links to trick the MSI installer into deleting files in locations that the attacker would otherwise have no access to. By creating a symlink from the world-writable directory to the target file, the attacker can manipulate the MSI installer's repair functionality to delete the target file during the repair process. Exploitation of this vulnerability could allow an attacker to delete important system files or replace them with malicious files, potentially leading to the affected device being compromised. The cloudflared client itself is not affected by this vulnerability, only the installer for 32-bit Windows devices.

Due to a misconfiguration in the manifest file of the WARP client for Android, it was possible to a perform a task hijacking attack. An attacker could create a malicious mobile application which could hijack legitimate app and steal potentially sensitive information when installed on the victim's device.

support_uri parameter in the WARP client local settings file (mdm.xml) lacked proper validation which allowed for privilege escalation and launching an arbitrary executable on the local machine upon clicking on the "Send feedback" option. An attacker with access to the local file system could use a crafted XML config file pointing to a malicious file or set a local path to the executable using Cloudflare Zero Trust Dashboard (for Zero Trust enrolled clients).

LZ4 bindings use a deprecated C API that is vulnerable to memory corruption, which could lead to arbitrary code execution if called with untrusted user input.

Using warp-cli command "add-trusted-ssid", a user was able to disconnect WARP client and bypass the "Lock WARP switch" feature resulting in Zero Trust policies not being enforced on an affected endpoint.

It was possible for a user to delete a VPN profile from WARP mobile client on iOS platform despite the Lock WARP switch https://developers.cloudflare.com/cloudflare-one/connections/connect-devices/warp/warp-settings/#lock-warp-switch  feature being enabled on Zero Trust Platform. This led to bypassing policies and restrictions enforced for enrolled devices by the Zero Trust platform.

Lock Warp switch is a feature of Zero Trust platform which, when enabled, prevents users of enrolled devices from disabling WARP client. Due to insufficient policy verification by WARP iOS client, this feature could be bypassed by using the "Disable WARP" quick action.

It was possible to bypass Lock WARP switch feature https://developers.cloudflare.com/cloudflare-one/connections/connect-devices/warp/warp-settings/#lock-warp-switch  on the WARP iOS mobile client by enabling both "Disable for cellular networks" and "Disable for Wi-Fi networks" switches at once in the application settings. Such configuration caused the WARP client to disconnect and allowed the user to bypass restrictions and policies enforced by the Zero Trust platform.

It was possible to bypass policies configured for Zero Trust Secure Web Gateway by using warp-cli 'set-custom-endpoint' subcommand. Using this command with an unreachable endpoint caused the WARP Client to disconnect and allowed bypassing administrative restrictions on a Zero Trust enrolled endpoint.

Attackers can create long chains of CAs that would lead to OctoRPKI exceeding its max iterations parameter. In consequence it would cause the program to crash, preventing it from finishing the validation and leading to a denial of service. Credits to Donika Mirdita and Haya Shulman - Fraunhofer SIT, ATHENE, who discovered and reported this vulnerability.

sflow decode package does not employ sufficient packet sanitisation which can lead to a denial of service attack. Attackers can craft malformed packets causing the process to consume large amounts of memory resulting in a denial of service.

By using warp-cli subcommands (disable-ethernet, disable-wifi), it was possible for a user without admin privileges to bypass configured Zero Trust security policies (e.g. Secure Web Gateway policies) and features such as 'Lock WARP switch'.