CVE-2026-50012

Squid is a caching proxy for the Web. Prior to 7.6, due to an improper input validation bug in cache digest reply handling (peerDigestSwapInMask in src/peer_digest.cc), Squid is vulnerable to a heap-based buffer overflow: a cache digest's on-the-wire size may be larger than the mask_size declared within the digest, so a trusted peer sending a maliciously crafted reply to a cache_digest request message can trigger the overflow. This attack is limited to Squid instances compiled with the --enable-cache-digests option and configured with cache_peer entries. This issue is fixed in version 7.6.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/squid-cache/squid/commit/19fcfe922717c8b255270c032dcde4071c003bcd	Patch
https://github.com/squid-cache/squid/pull/2423	Patch
https://github.com/squid-cache/squid/releases/tag/SQUID_7_6	Release Notes
https://github.com/squid-cache/squid/security/advisories/GHSA-5vmx-9x64-9284	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-07-16 17:16

Updated : 2026-07-20 01:35

NVD link : CVE-2026-50012

Mitre link : CVE-2026-50012

CVE.ORG link : CVE-2026-50012

JSON object : View

Products Affected

squid-cache

squid

CWE

CWE-20

Improper Input Validation

CWE-122

Heap-based Buffer Overflow

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