CVE-2026-47729

medium

Description

Squid is a caching proxy for the Web. Prior to 7.6, due to an improper validation of syntactic correctness of input in the FTP gateway (src/clients/FtpGateway.cc), Squid is vulnerable to an out-of-bounds read: when a listing entry date in the TypeA or TypeB directory-listing formats is not followed by a filename, parsing was not restricted to the input buffer, so a trusted client accessing a misbehaving FTP server through Squid's gateway feature could read memory from random unrelated transactions. This issue is fixed in version 7.6.

https://www.theregister.com/security/2026/06/23/mythos-discovers-squidbleed-a-memory-leak-thats-gone-undetected-since-clinton-era/5260367

https://www.securityweek.com/decades-old-squid-proxy-flaw-squidbleed-can-expose-user-data/

https://thehackernews.com/2026/06/29-year-old-squid-proxy-bug-squidbleed.html

https://github.com/squid-cache/squid/security/advisories/GHSA-8c37-pxjq-qwrg

https://github.com/squid-cache/squid/releases/tag/SQUID_7_6

https://github.com/squid-cache/squid/pull/2409

https://github.com/squid-cache/squid/pull/2408

https://github.com/squid-cache/squid/commit/865a131c7d557e68c965043d98c2eccae26deef8

Details

Source: Mitre, NVD

Published: 2026-07-16

Updated: 2026-07-20

Named Vulnerability: Squidbleed

Risk Information

CVSS v2

Base Score: 6.8

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 6.5

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

Severity: Medium

EPSS

EPSS: 0.01907

Vulnerability Watch

Tenable Research has classified this CVE under the following Vulnerability Watch classification, which includes active and historical (inactive) classifications. You can learn more about these classifications on our blog.

Vulnerability Being Monitored

Detections

Analytics