Ubuntu Squid Update Fixes HTTP and Cache Issues on Ubuntu Systems

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Several security issues were fixed in Squid. Software Description: - squid: Web proxy cache server - squid3: Web proxy cache server Details: It was discovered that Squid incorrectly handled certain HTTP Transfer- Encoding headers. An attacker could possibly use this issue to perform HTTP request smuggling attacks, bypass security mechanisms, or poison web caches. (CVE-2026-61642) It was discovered that Squid incorrectly handled certain cache digest replies, which could lead to a buffer overflow. A remote attacker could possibly use this issue to cause Squid to crash, resulting in a denial of service. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-50012) It was discovered that Squid incorrectly handled parsing certain FTP directory listings. A remote attacker could possibly use this issue to obtain sensitive information. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-47729) It was disc... Read the Full Advisory

Several security issues were fixed in Squid.

Software Description:

- squid: Web proxy cache server

- squid3: Web proxy cache server

It was discovered that Squid incorrectly handled certain HTTP Transfer-

Encoding headers. An attacker could possibly use this issue to perform HTTP

request smuggling attacks, bypass security mechanisms, or poison web

caches. (CVE-2026-61642)

It was discovered that Squid incorrectly handled certain cache digest

replies, which could lead to a buffer overflow. A remote attacker could

possibly use this issue to cause Squid to crash, resulting in a denial of

service. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and

Ubuntu 20.04 LTS. (CVE-2026-50012)

It was discovered that Squid incorrectly handled parsing certain FTP

directory listings. A remote attacker could possibly use this issue to

obtain sensitive information. This issue only affected Ubuntu 16.04 LTS,

Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2026-47729)

The problem can be corrected by updating your system to the following package versions: Ubuntu 24.04 LTS squid 6.14-0ubuntu0.24.04.5 squid-openssl 6.14-0ubuntu0.24.04.5 Ubuntu 22.04 LTS squid 5.9-0ubuntu0.22.04.8 squid-openssl 5.9-0ubuntu0.22.04.8 Ubuntu 20.04 LTS squid 4.10-1ubuntu1.13+esm3 Available with Ubuntu Pro Ubuntu 18.04 LTS squid 3.5.27-1ubuntu1.14+esm6 Available with Ubuntu Pro Ubuntu 16.04 LTS squid 3.5.12-1ubuntu7.16+esm7 Available with Ubuntu Pro In general, a standard system update will make all the necessary changes.

CVE-2026-32748, CVE-2026-33515, CVE-2026-33526, CVE-2026-47729,

CVE-2026-50012, CVE-2026-61642

Ubuntu Security Notice USN-8941-1

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