CVE-2026-55202 (GCVE-0-2026-55202)

Vulnerability from cvelistv5 – Published: 2026-06-17 19:13 – Updated: 2026-06-17 19:45 X_Open Source
VLAI
Title
Tinyproxy - Stathost Detection Bypass via Host Header Manipulation
Summary
Tinyproxy through 1.11.3, fixed in commit 09312a1, fails to properly validate the Host header during stathost detection, allowing unauthenticated attackers to access the stats page by injecting a matching Host header or bypass detection via port manipulation. Remote attackers can trigger unauthorized access to internal proxy statistics or misroute requests as transparent proxy connections to circumvent access controls.
Severity
8.8 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
8.2 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
CWE
  • CWE-290 - Authentication Bypass by Spoofing
Assigner
References
Impacted products
Vendor Product Version
tinyproxy tinyproxy Affected: 0 , ≤ 1.11.3 (semver)
Unaffected: 09312a185ae25cc486b4ff5987638a7917a48bce (git)
Create a notification for this product.
Date Public
2026-04-17 00:00
Show details on NVD website
To clipboard 

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            "Recovery": "NOT_DEFINED",
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          "url": "https://github.com/tinyproxy/tinyproxy/pull/606"
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      "title": "Tinyproxy - Stathost Detection Bypass via Host Header Manipulation",
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  "cveMetadata": {
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    "datePublished": "2026-06-17T19:13:45.383Z",
    "dateReserved": "2026-06-16T15:53:37.764Z",
    "dateUpdated": "2026-06-17T19:45:15.614Z",
    "state": "PUBLISHED"
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