CVE-2026-125371

medium

Description

Tinyproxy through 1.11.3 contains an access control bypass vulnerability in acl_string_processing() in src/acl.c that compares only trailing hostname characters without checking DNS label boundaries. Attackers controlling the PTR record for their source IP, such as untrusted.net, can satisfy an 'Allow trusted.net' entry to use the proxy despite deny-by-default ACLs.

References

https://www.vulncheck.com/advisories/tinyproxy-through-1.11.3-hostname-acl-allow-list-bypass-via-suffix-match

https://github.com/tinyproxy/tinyproxy/issues/627

https://github.com/tinyproxy/tinyproxy/commit/3991ac8f98c6a9f05b3265018b812dbf2ca92c28

https://github.com/tinyproxy/tinyproxy/blob/1.11.3/src/acl.c#L156-L174

https://github.com/tinyproxy/tinyproxy

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-120534

Details

Source: Mitre, NVD

Published: 2026-11-10

Updated: 2026-11-10

Risk Information

CVSS v2

Base Score: 4

Vector: CVSS2#AV:N/AC:H/Au:N/C:P/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 4.8

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

Severity: Medium

CVSS v4

Base Score: 6.3

Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

Severity: Medium

EPSS

EPSS: 0.00279