Is CVE-2026-33526 actively exploited?

CVE-2026-33526 has no public evidence of in-the-wild exploitation as of 2026-03-31.

What is the CVSS score for CVE-2026-33526?

CVE-2026-33526 has a CVSS score of 9.2 (CRITICAL severity). Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/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-2026-33526?

Patch guidance is available from squid-cache security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2026-33526.

Fix CVE-2026-33526 - CRITICAL squid-cache squid

Description

Squid is a caching proxy for the Web. Prior to version 7.5, due to heap Use-After-Free, Squid is vulnerable to Denial of Service when handling ICP traffic. This problem allows a remote attacker to perform a reliable and repeatable Denial of Service attack against the Squid service using ICP protocol. This attack is limited to Squid deployments that explicitly enable ICP support (i.e. configure non-zero `icp_port`). This problem _cannot_ be mitigated by denying ICP queries using `icp_access` rules. Version 7.5 contains a patch.

CVSS Metrics

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/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-416 · Use After Free CWE-826

Metadata

Primary Vendor: SQUID-CACHE
Published: 3/26/2026
Last Modified: 3/31/2026
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

Affected Products

squid-cache : squid

Remediation Guidance

Executive Summary

Cite this page

CVE-2026-33526. CVEDatabase.com. Retrieved 1 May 2026. https://cvedatabase.com/cve/CVE-2026-33526

View on NIST NVD

CVE-2026-33526 vulnerability