CVE-2026-47729

MEDIUM

Squid: Memory disclosure in FTP gateway

Title source: cna
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2026-47729. PoCs published by 0xBlackash.

AI-analyzed exploit summary This PoC exploits CVE-2026-47729 (Squidbleed), a heap buffer over-read vulnerability in Squid proxy, by setting up a malicious FTP server that sends truncated directory listings to leak adjacent memory containing credentials (Basic Auth/Bearer tokens). The exploit uses multi-threaded polling to harvest leaked data from the target Squid instance.

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.

Exploits (1)

nomisec WORKING POC 5 stars
by 0xBlackash · poc
https://github.com/0xBlackash/CVE-2026-47729

This PoC exploits CVE-2026-47729 (Squidbleed), a heap buffer over-read vulnerability in Squid proxy, by setting up a malicious FTP server that sends truncated directory listings to leak adjacent memory containing credentials (Basic Auth/Bearer tokens). The exploit uses multi-threaded polling to harvest leaked data from the target Squid instance.

Classification
Working Poc 98%
Attack Type
Info Leak
Complexity
Moderate
Reliability
Reliable
Target: Squid proxy (versions affected by CVE-2026-47729)
No auth needed
Prerequisites: Network access to a vulnerable Squid proxy instance · Ability to run a local FTP server on the attacker's machine
mistral-large-3 · analyzed Jul 24, 2026 Full analysis →

Scores

CVSS v3 6.5
EPSS 0.0150
EPSS Percentile 71.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-125 CWE-1289
Status published
Products (1)
squid-cache/squid < 7.6 (2 CPE variants)
Published Jul 16, 2026
Tracked Since Jul 16, 2026