RHSA-2026:98537HighCVSS 7.7

Red Hat Security Advisory: squid security update

Published
November 11, 2026
Last Modified
November 11, 2026

🔗 CVE IDs covered (1)

CVE-2026-61642 →

📋 Description

CVE-2026-61642 — squid: squid: Request Smuggling in HTTP Transfer-Encoding

🎯 Affected products14

  • Red Hat Enterprise Linux AppStream (v. 9)
  • squid-7:5.5-27.el9_9.1.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-7:5.5-27.el9_9.1.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-7:5.5-27.el9_9.1.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-7:5.5-27.el9_9.1.src as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-7:5.5-27.el9_9.1.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-debuginfo-7:5.5-27.el9_9.1.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-debuginfo-7:5.5-27.el9_9.1.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-debuginfo-7:5.5-27.el9_9.1.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-debuginfo-7:5.5-27.el9_9.1.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-debugsource-7:5.5-27.el9_9.1.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-debugsource-7:5.5-27.el9_9.1.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-debugsource-7:5.5-27.el9_9.1.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • squid-debugsource-7:5.5-27.el9_9.1.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)

✅ Remediation

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Workaround: To mitigate this vulnerability, administrators should enforce rigorous server-side HTTP header validation by explicitly denying conflicting or ambiguous framing requests. In your squid.conf, this can be temporarily achieved by rejecting the problematic encoding outright using the directive request_header_access Transfer-Encoding deny all. Alternatively, administrators can neutralize the request smuggling attack vector entirely by disabling connection reuse with the settings client_persistent_connections off and server_persistent_connections off.

🔗 References (4)