CVE-2019-18676

moderate-risk

Published 2019-11-26

An issue was discovered in Squid 3.x and 4.x through 4.8. Due to incorrect input validation, there is a heap-based buffer overflow that can result in Denial of Service to all clients using the proxy. Severity is high due to this vulnerability occurring before normal security checks; any remote client that can reach the proxy port can trivially perform the attack via a crafted URI scheme.

Do I need to act?

1.4% chance of exploitation in next 30 days

EPSS score — moderate exploit probability

Not on CISA KEV list

No confirmed active exploitation reported to CISA

Patch status unknown

Check vendor advisories for fix availability and mitigation guidance

CVSS 7.5/10 High

NETWORK / LOW complexity

Affected Products (10)

Squid

Ubuntu Linux

Fedora

Debian Linux

Ubuntu Linux

Affected Vendors

Debian Canonical Squid-Cache Fedoraproject

References (20)

Third Party Advisory http://www.squid-cache.org/Advisories/SQUID-2019_8.txt

Patch http://www.squid-cache.org/Versions/v4/changesets/squid-4-fbbdf75efd7a5cc244b488...

Issue Tracking https://bugzilla.suse.com/show_bug.cgi?id=1156329

Patch https://github.com/squid-cache/squid/pull/275

Mailing List https://lists.debian.org/debian-lts-announce/2020/07/msg00009.html

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro...

Third Party Advisory https://usn.ubuntu.com/4213-1/

Third Party Advisory https://usn.ubuntu.com/4446-1/

Third Party Advisory https://www.debian.org/security/2020/dsa-4682