CVE-2026-50012
Publication date 12 June 2026
Last updated 21 October 2026
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| squid | 26.10 stonking |
Not affected
|
| 26.04 LTS resolute |
Fixed in 7.2-2ubuntu2.2
|
|
| 24.04 LTS noble |
Fixed in 6.14-0ubuntu0.24.04.4
|
|
| 22.04 LTS jammy |
Fixed in 5.9-0ubuntu0.22.04.7
|
|
| 20.04 LTS focal |
Fixed in 4.10-1ubuntu1.13+esm3
|
|
| squid3 | 26.10 stonking | Not in release |
| 26.04 LTS resolute | Not in release | |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| 18.04 LTS bionic |
Fixed in 3.5.27-1ubuntu1.14+esm6
|
|
| 16.04 LTS xenial |
Fixed in 3.5.12-1ubuntu7.16+esm7
|
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CVSS version: CVSS v3.0
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
References
Related Ubuntu Security Notices (USN)
- USN-8941-1
- Squid vulnerabilities
- 20 October 2026