CVE-2026-33526

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2026-33526
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.

7.5 /10

CVSS v3 : HIGH

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://github.com/squid-cache/squid/commit/8a7d42f9d44befb8fcbbb619505587c8de6a1e91 Patch
https://github.com/squid-cache/squid/security/advisories/GHSA-hpfx-h48q-gvwg Vendor Advisory
http://www.openwall.com/lists/oss-security/2026/03/25/2 Third Party Advisory
Configurations

Configuration 1 (hide)

cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
History

31 Mar 2026, 01:18

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 7.5
References () https://github.com/squid-cache/squid/commit/8a7d42f9d44befb8fcbbb619505587c8de6a1e91 - () https://github.com/squid-cache/squid/commit/8a7d42f9d44befb8fcbbb619505587c8de6a1e91 - Patch
References () https://github.com/squid-cache/squid/security/advisories/GHSA-hpfx-h48q-gvwg - () https://github.com/squid-cache/squid/security/advisories/GHSA-hpfx-h48q-gvwg - Vendor Advisory
References () http://www.openwall.com/lists/oss-security/2026/03/25/2 - () http://www.openwall.com/lists/oss-security/2026/03/25/2 - Third Party Advisory
First Time Squid-cache squid
Squid-cache
Summary
  • (es) Squid es un proxy de almacenamiento en caché para la Web. Antes de la versión 7.5, debido a un uso después de liberación (Use-After-Free) en el heap, Squid es vulnerable a denegación de servicio al manejar tráfico ICP. Este problema permite a un atacante remoto realizar un ataque de denegación de servicio fiable y repetible contra el servicio Squid utilizando el protocolo ICP. Este ataque se limita a implementaciones de Squid que habilitan explícitamente el soporte ICP (es decir, configuran un 'icp_port' distinto de cero). Este problema _no puede_ mitigarse denegando consultas ICP utilizando reglas de 'icp_access'. La versión 7.5 contiene un parche.
CPE cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*

26 Mar 2026, 01:16

Type Values Removed Values Added
New CVE
Information

Published : 2026-03-26 01:16

Updated : 2026-03-31 01:18

NVD link : CVE-2026-33526

Mitre link : CVE-2026-33526

CVE.ORG link : CVE-2026-33526

JSON object : View

Products Affected

squid-cache

  • squid
CWE
CWE-416

Use After Free

CWE-826

Premature Release of Resource During Expected Lifetime