CVE-2025-54574

Description

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.

CVSS v3.1 Score

9.3

CRITICAL

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

Weakness Type (CWE)

CWE-122 CWE-122

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
squid-cache	squid	< 6.4

References

Advisories & Patches

https://github.com/squid-cache/squid/commit/a27bf4b84da23594150c7a86a23435df0b35b988 https://github.com/squid-cache/squid/security/advisories/GHSA-w4gv-vw3f-29g3

Other References

https://github.com/squid-cache/squid/releases/tag/SQUID_6_4 http://www.openwall.com/lists/oss-security/2025/11/05/5 https://lists.debian.org/debian-lts-announce/2025/09/msg00027.html

Frequently Asked Questions

What is CVE-2025-54574? +

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. It has a CVSS v3.1 base score of 9.3 (CRITICAL).

How severe is CVE-2025-54574? +

CVE-2025-54574 has a CVSS v3.1 score of 9.3 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2025-54574? +

CVE-2025-54574 affects products from squid-cache, specifically: squid. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-54574? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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