CVE-2019-12526

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 20.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-11-26 · updated 2026-06-17
Weakness: CWE-787

Description

An issue was discovered in Squid before 4.9. URN response handling in Squid suffers from a heap-based buffer overflow. When receiving data from a remote server in response to an URN request, Squid fails to ensure that the response can fit within the buffer. This leads to attacker controlled data overflowing in the heap.

Affected products

Canonical Ubuntu Linux: 16.04, 18.04, 19.04, 19.10
Debian Linux: 8.0, 9.0, 10.0
Fedoraproject Fedora: 30, 31
openSUSE Leap: 15.0
Squid: from 3.0 through 3.5.28; from 4.0 through 4.8

References

http://www.squid-cache.org/Advisories/SQUID-2019_7.txt
https://bugzilla.suse.com/show_bug.cgi?id=1156326
https://lists.debian.org/debian-lts-announce/2019/12/msg00011.html
https://lists.debian.org/debian-lts-announce/2020/07/msg00009.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MTM74TU2BSLT5B3H4F3UDW53672NVLMC/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UEMOYTMCCFWK5NOXSXEIH5D2VGWVXR67/
https://security.gentoo.org/glsa/202003-34
https://usn.ubuntu.com/4213-1/
https://www.debian.org/security/2020/dsa-4682
http://www.squid-cache.org/Advisories/SQUID-2019_7.txt
https://bugzilla.suse.com/show_bug.cgi?id=1156326
https://lists.debian.org/debian-lts-announce/2019/12/msg00011.html

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