CVE-2026-33515

Publication date 26 March 2026

Last updated 15 October 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

6.5 · Medium

Score breakdown

Description

Squid is a caching proxy for the Web. Prior to version 7.5, due to improper input validation, Squid is vulnerable to out of bounds read when handling ICP traffic. This problem allows a remote attacker to receive small amounts of memory potentially containing sensitive information when responding with errors to invalid ICP requests. 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.

Status

Package Ubuntu Release Status
squid 26.10 stonking
Not affected
26.04 LTS resolute
Not affected
25.10 questing
Fixed in 6.14-0ubuntu0.25.10.2
24.04 LTS noble
Fixed in 6.14-0ubuntu0.24.04.2
22.04 LTS jammy
Fixed in 5.9-0ubuntu0.22.04.5
20.04 LTS focal
Vulnerable
squid3 26.10 stonking Not in release
26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
18.04 LTS bionic
Vulnerable
16.04 LTS xenial
Vulnerable

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
squid

Severity score breakdown

CVSS version:

Base score 6.9 · Medium

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:N/SA:N

Base score 6.5 · Medium

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

References

Related Ubuntu Security Notices (USN)

Other references

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