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 3.1

5.5CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H

EPSS

1.4% chance of exploitation in the next 30 days; higher than 71% of CVEs (scores of 2026-10-25)

CWEs

CWE-20, CWE-122

Published

2026-07-16

Modified

2026-10-24

Record from

the NVD, synced 2026-10-25

Affected

• squid-cache:squid

References

• https://github.com/squid-cache/squid/commit/19fcfe922717c8b255270c032dcde4071c003bcd
• https://github.com/squid-cache/squid/pull/2423
• https://github.com/squid-cache/squid/releases/tag/SQUID_7_6
• https://github.com/squid-cache/squid/security/advisories/GHSA-5vmx-9x64-9284

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