Description
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.
Severity (CVSS)
| Base score | 5.5 |
|---|---|
| Severity | Medium |
| Version | CVSS 3.1 |
| Vector | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H |
| Provided by | CNA |
Weaknesses
- CWE-20 — CWE-20: Improper Input Validation
- CWE-122 — CWE-122: Heap-based Buffer Overflow
Affected products
| Vendor | Product | Versions |
|---|---|---|
| squid-cache | squid | < 7.6 |
References
- https://github.com/squid-cache/squid/security/advisories/GHSA-5vmx-9x64-9284 (x_refsource_CONFIRM)
- https://github.com/squid-cache/squid/pull/2423 (x_refsource_MISC)
- https://github.com/squid-cache/squid/commit/19fcfe922717c8b255270c032dcde4071c003bcd (x_refsource_MISC)
- https://github.com/squid-cache/squid/releases/tag/SQUID_7_6 (x_refsource_MISC)
Generated from the official CVE List on 17 Jul 2026 07:01 UTC.