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CVE-2026-125371

6.3 mediumEPSS 0.3%

Medium (6.3) in tinyproxy tinyproxy. EPSS 0.3% estimated probability of exploitation activity in the next 30 days.

On this page
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.

Severity

CVSS 4.0

6.3 medium
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

CVSS 3.1

4.8 medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS
0.3% estimated probability of exploitation activity in the next 30 days; 21st percentile. Scored 2026-11-10. A forecast for this CVE across the internet, not for your own systems.
CWE
CWE-187 Partial String Comparison
Published
Assigned by
VulnCheck (CNA)
NVD analysis
Awaiting analysis
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
tinyproxythrough 1.11.3

Linux distributions

DistributionReleasePackageFixed inAdvisory
Debian12, 13, 14tinyproxyno fix listedDEBIAN-CVE-2026-125371

From the distributions' data via OSV.dev: the Debian Security Tracker. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian.

References

Check your stackJSON