Is CVE-2026-35391 actively exploited?

CVE-2026-35391 has no public evidence of in-the-wild exploitation as of 2026-04-09.

What is the CVSS score for CVE-2026-35391?

CVE-2026-35391 has a CVSS score of 8.7 (HIGH severity). Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X.

How do I patch CVE-2026-35391?

Patch guidance is available from bulwarkmail security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2026-35391.

Which products are affected by CVE-2026-35391?

1 product: bulwarkmail webmail.

Fix CVE-2026-35391 - HIGH bulwarkmail webmail

Description

Bulwark Webmail is a self-hosted webmail client for Stalwart Mail Server. Prior to 1.4.11, the getClientIP() function in lib/admin/session.ts trusted the first (leftmost) entry of the X-Forwarded-For header, which is fully controlled by the client. An attacker could forge their source IP address to bypass IP-based rate limiting (enabling brute-force attacks against the admin login) or forge audit log entries (making malicious activity appear to originate from arbitrary IP addresses). This vulnerability is fixed in 1.4.11.

CVSS Metrics

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector: network
Complexity: low
Privileges: none
User Action: none
Confidentiality: undefined
Integrity: undefined
Availability: undefined
Weaknesses: CWE-348

Metadata

Primary Vendor: BULWARKMAIL
Published: 4/6/2026
Last Modified: 4/9/2026
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

CVE-2026-35391

Description

CVSS Metrics

Metadata

Affected Products

Remediation Guidance

Executive Summary