CVE-2026-50012

Published Jul 16, 2026

Last updated 7 days ago

CVSS medium 5.5

Overview

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.
Source
security-advisories@github.com
NVD status
Analyzed
Products
squid

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
4.2
Exploitability score
1.2
Vector string
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H
Severity
MEDIUM

Weaknesses

security-advisories@github.com
CWE-20

Social media

Hype score
Not currently trending

  1. 2 CVEs in Squid https://t.co/wpCWKt89Sz CVE-2026-47729: Out-of-Bounds Read from random unrelated transactions when accessing a misbehaving FTP server CVE-2026-50012: Heap-based Buffer Overflow when sending maliciously crafted replies to cache_digest request messages, fixed in 7.6

    @oss_security

    18 Jun 2026

    303 Impressions

    2 Retweets

    5 Likes

    0 Bookmarks

    0 Replies

    0 Quotes

  2. プロキシサーバーSquid がFTPゲートウェイの境界外読み取り（CVE-2026-47729）とcache_digestのヒープバッファオーバーフロー（CVE-2026-50012）の脆弱性を修正 https://t.co/mie3ulqIJp #セキュリティ対策Lab #security #securitynews

    @securityLab_jp

    17 Jun 2026

    79 Impressions

    0 Retweets

    0 Likes

    0 Bookmarks

    0 Replies

    0 Quotes

  3. Squid 7.6 patches two memory bugs: CVE-2026-47729, an out-of-bounds read in the FTP gateway triggered by a misbehaving upstream FTP server, and CVE-2026-50012, a heap overflow in cache digests on --enable-cache-digests builds. If your proxy still gateways FTP, why is it still on?

    @canartuc

    15 Jun 2026

    29 Impressions

    0 Retweets

    0 Likes

    0 Bookmarks

    0 Replies

    0 Quotes

  4. 脆弱性についての正式発表はまだだが、6/7にリリースされたSquidのv7.6で修正された脆弱性2件の情報が解禁。 oss-sec: Squid CVE-2026-47729 and CVE-2026-50012 https://t.co/4w1lTsJx5Q

    @autumn_good_35

    15 Jun 2026

    380 Impressions

    0 Retweets

    2 Likes

    0 Bookmarks

    0 Replies

    0 Quotes

Configurations

Related CVEs

  1. 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.•CVE-2026-47729
  2. Squid is a caching proxy for the Web. Prior to version 7.5, due to heap Use-After-Free, Squid is vulnerable to Denial of Service when handling ICP traffic. This problem allows a remote attacker to perform a reliable and repeatable Denial of Service attack against the Squid service using ICP protocol. This attack is limited to Squid deployments that explicitly enable ICP support (i.e. configure non-zero `icp_port`). This problem _cannot_ be mitigated by denying ICP queries using `icp_access` rules. Version 7.5 contains a patch.•CVE-2026-33526
  3. Squid is a caching proxy for the Web. Prior to version 7.5, due to improper input validation, Squid is vulnerable to out of bounds read when handling ICP traffic. This problem allows a remote attacker to receive small amounts of memory potentially containing sensitive information when responding with errors to invalid ICP requests. This attack is limited to Squid deployments that explicitly enable ICP support (i.e. configure non-zero `icp_port`). This problem cannot be mitigated by denying ICP queries using `icp_access` rules. Version 7.5 contains a patch.•CVE-2026-33515
  4. Squid is a caching proxy for the Web. Prior to version 7.5, due to premature release of resource during expected lifetime and heap Use-After-Free bugs, Squid is vulnerable to Denial of Service when handling ICP traffic. This problem allows a remote attacker to perform a reliable and repeatable Denial of Service attack against the Squid service using ICP protocol. This attack is limited to Squid deployments that explicitly enable ICP support (i.e. configure non-zero `icp_port`). This problem _cannot_ be mitigated by denying ICP queries using `icp_access` rules. This bug is fixed in Squid version 7.5.•CVE-2026-32748
  5. Squid is a caching proxy for the Web. In Squid versions prior to 7.2, a failure to redact HTTP authentication credentials in error handling allows information disclosure. The vulnerability allows a script to bypass browser security protections and learn the credentials a trusted client uses to authenticate. This potentially allows a remote client to identify security tokens or credentials used internally by a web application using Squid for backend load balancing. These attacks do not require Squid to be configured with HTTP authentication. The vulnerability is fixed in version 7.2. As a workaround, disable debug information in administrator mailto links generated by Squid by configuring squid.conf with email_err_data off.•CVE-2025-62168

References

Sources include official advisories and independent security research.