Vulnerability record · CVE-2025-54574 · published 1 August 2025

CVE-2025-54574: Squid-cache squid heap-based buffer overflow vulnerability

Squid Cache · Squid

Squid is a caching proxy for the Web. In versions 6.3 and below, Squid is vulnerable to a heap buffer overflow and possible remote code execution attack when processing URN due to incorrect buffer management. This has been fixed in version 6.4. To work around this issue, disable URN access permissions.

9.8 CVSS 3.1 Critical EPSS 23% · top 2.3% CWE-122 · Heap-based buffer overflowCWE-787 · Out-of-bounds write

9.8CVSS 3.1 base score

23%EPSS exploitation probability, 30 days

NoNot in CISA KEV

1Affected product versions listed by NVD

5References

17 Jun 2026Last modified by NVD

Description

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

Squid Squid Cache

References

Link	Tags
https://github.com/squid-cache/squid/commit/a27bf4b84da23594150c7a86a23435df0b35b988	Patch
https://github.com/squid-cache/squid/releases/tag/SQUID_6_4	Release Notes
https://github.com/squid-cache/squid/security/advisories/GHSA-w4gv-vw3f-29g3	MitigationPatchVendor Advisory
http://www.openwall.com/lists/oss-security/2025/11/05/5
https://lists.debian.org/debian-lts-announce/2025/09/msg00027.html

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2025-54574), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.