Squid's URN Handling can lead to Buffer Overflow (squid-cache squid)

CVE-2025-54574

CRITICAL 9.3

At a glance

Source: NVD
EPSS: EPSS 23.96 % · percentile 98 (2026-10-31)
State: PUBLISHED
Published: 2025-08-01 18:02 UTC
Updated: 2025-11-05 17:04 UTC
Assigner: GitHub_M
NVD status: Modified

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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.

Weaknesses (CWE)

CWE-122 — Heap-based Buffer Overflow
CWE-787 — Out-of-bounds Write

References

Scores

Version	Score	Vector	Scored by
CVSS 3.1	CRITICAL 9.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:H	GitHub_M
CVSS 3.1	CRITICAL 9.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:H	NVD · security-advisories@github.com (Secondary)
CVSS 3.1	CRITICAL 9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	NVD · nvd@nist.gov (Primary)

European references

ENISA EUVD · EUVD-2025-23392
GCVE · GCVE-0-2025-54574

CERT-FR advisories

CERTFR-2025-AVI-0647 — Vulnérabilité dans Squid · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:* < 6.4

Affected products

Product	Versions
squid-cache · squid	affected < 6.4

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD

💣 Squid's URN Handling can lead to Buffer Overflow (squid-cache squid)