CVE-2026-125371 (GCVE-0-2026-125371)

Vulnerability from cvelistv5 – Published: 2026-11-09 23:27 – Updated: 2026-11-09 23:27
VLAI
Title
Tinyproxy through 1.11.3 Hostname ACL Allow-List Bypass via Suffix Match
Summary
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
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
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
CWE
  • CWE-187 - Partial String Comparison
Assigner
VulnCheck CNA
References
Impacted products
Vendor Product Version
tinyproxy tinyproxy Affected: 0 , ≤ 1.11.3 (semver)
Unaffected: 3991ac8f98c6a9f05b3265018b812dbf2ca92c28 (git)
    cpe:2.3:a:tinyproxy_project:tinyproxy:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-14 00:00
Credits
Yuri Bichuk
Show details on NVD website
To clipboard 

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          "vendor": "tinyproxy",
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        }
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        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
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        },
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          "url": "https://www.vulncheck.com/advisories/tinyproxy-through-1.11.3-hostname-acl-allow-list-bypass-via-suffix-match"
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  "cveMetadata": {
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    "dateReserved": "2026-11-09T22:03:04.330Z",
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    "state": "PUBLISHED"
  },
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