Description
The httpProcessReplyHeader function in http.c for Squid 2.5-STABLE7 and earlier does not properly set the debug context when it is handling "oversized" HTTP reply headers, which might allow remote attackers to poison the cache or bypass access controls based on header size.
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 | 2.5.7-7 | — |
| Debian 13 | squid | 2.5.7-7 | — |
| Debian 12 | squid | 2.5.7-7 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 4 | squid | 7:2.5.STABLE6-3.4E.3 | RHSA-2005:060 |
| RHEL 3 | squid | 7:2.5.STABLE3-6.3E.7 | RHSA-2005:061 |
Advisories 2
- RHSA-2005:060 Red Hat Security Advisory: squid security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2005:061 Red Hat Security Advisory: squid security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
References
- 14091 third-party-advisory
- VU#823350 third-party-advisory
- 12412 vdb-entry
- http://www.squid-cache.org/bugs/show_bug.cgi?id=1216
- oval:org.mitre.oval:def:10998 vdb-entry signature
- FLSA-2006:152809 vendor-advisory
- RHSA-2005:061 vendor-advisory
- squid-http-cache-poisoning(19060) vdb-entry
- CLA-2005:931 vendor-advisory
- http://www.squid-cache.org/Versions/v2/2.5/bugs/#squid-2.5.STABLE7-oversize_reply_headers
- SUSE-SA:2005:006 vendor-advisory
- RHSA-2005:060 vendor-advisory
- http://www.squid-cache.org/Versions/v2/2.5/bugs/squid-2.5.STABLE7-oversize_reply_headers.patch