CVE-2026-33526
Estado: ModificadaCrítica (9.2)—
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
- Versión: 4.0
- 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
- Puntuación base: 9.2
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 13%
- Percentil entre todas las CVEs puntuadas: 96
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access85 % - Impacto principal
T1499.004Application or System Exploitationimpact90 %
Vector AV:N/PR:N/UI:N indica explotación remota sin privilegios (T1190). El ataque remoto vía protocolo ICP causa denegación de servicio confiable en Squid, clasificado como T1499.004 (Flood de protocolo).
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-416, CWE-826
- CWE-825
Referencias
- https://github.com/squid-cache/squid/commit/8a7d42f9d44befb8fcbbb619505587c8de6a1e91
- https://github.com/squid-cache/squid/security/advisories/GHSA-hpfx-h48q-gvwg
- http://www.openwall.com/lists/oss-security/2026/03/25/2
- https://access.redhat.com/errata/RHSA-2026:10255
- https://access.redhat.com/errata/RHSA-2026:10256
- https://access.redhat.com/errata/RHSA-2026:10257
- https://access.redhat.com/errata/RHSA-2026:11901
- https://access.redhat.com/errata/RHSA-2026:20564
- https://access.redhat.com/errata/RHSA-2026:20565
- https://access.redhat.com/errata/RHSA-2026:20580
- https://access.redhat.com/errata/RHSA-2026:6301
- https://access.redhat.com/errata/RHSA-2026:8119
- https://access.redhat.com/errata/RHSA-2026:8317
- https://access.redhat.com/errata/RHSA-2026:8880
- https://access.redhat.com/errata/RHSA-2026:9220
- https://access.redhat.com/security/cve/CVE-2026-33526
- https://bugzilla.redhat.com/show_bug.cgi?id=2451574
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33526.json
JSON original (NVD)
Mostrar
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