Buffer overflow in Squid-cache Squid
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…
Vulnerability class: Buffer Overflow
EPSS: 0.093 (92.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.3 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:H.
Affected products
- Squid-cache Squid — versions < 6.4
Weakness classification (CWE)
Public proof-of-concept exploits
References
- https://github.com/squid-cache/squid/security/advisories/GHSA-w4gv-vw3f-29g3 (x_refsource_CONFIRM)
- https://github.com/squid-cache/squid/commit/a27bf4b84da23594150c7a86a23435df0b35b988 (x_refsource_MISC)
- https://github.com/squid-cache/squid/releases/tag/SQUID_6_4 (x_refsource_MISC)
Frequently asked questions
- What is CVE-2025-54574?
- CVE-2025-54574 is a critical-severity vulnerability in Squid-cache Squid, classified under Heap-based Buffer Overflow. CVSS score: 9.3/10. Published 2025-08-01.
- How severe is CVE-2025-54574?
- Critical severity. CVSS v3 base score is 9.3 out of 10.
- Is CVE-2025-54574 known to be exploited?
- 7 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.