Buffer overflow in Squid-Cache Squid
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.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
EPSS: 0.014 (69.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H.
Affected products
- Squid-cache Squid — versions < 7.6
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-50012?
- CVE-2026-50012 is a medium-severity vulnerability in Squid-Cache Squid, classified under Improper Input Validation. CVSS score: 5.5/10. Published 2026-07-16.
- How severe is CVE-2026-50012?
- Medium severity. CVSS v3 base score is 5.5 out of 10.