Description
Squid 2.5.STABLE9 and earlier does not trigger a fatal error when it identifies missing or invalid ACLs in the http_access configuration, which could lead to less restrictive ACLs than intended by the administrator.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | squid | 2.5.9-7 | — |
| Debian 13 | squid | 2.5.9-7 | — |
| Debian 12 | squid | 2.5.9-7 | — |
| Debian 3.0 | squid | 2.4.6-2woody8 | DSA-721-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 4 | squid | 7:2.5.STABLE6-3.4E.9 | RHSA-2005:415 |
| RHEL 3 | squid | 7:2.5.STABLE3-6.3E.13 | RHSA-2005:415 |
Advisories 2
- RHSA-2005:415 Red Hat Security Advisory: squid security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DSA-721-1 squid - design flaw Debian Security (DSA / DLA) · Mar 9, 2026
References
- FLSA-2006:152809 vendor-advisory
- CLA-2005:948 vendor-advisory
- http://www.squid-cache.org/bugs/show_bug.cgi?id=1255
- http://www.squid-cache.org/Versions/v2/2.5/bugs/#squid-2.5.STABLE9-acl_error
- oval:org.mitre.oval:def:10513 vdb-entry signature
- RHSA-2005:415 vendor-advisory
- DSA-721 vendor-advisory