Critical 9.1Published Aug 12, 2026

CVE-2026-73501kin-openapi: ValidationHandler.Load() Fail-Open Authentication Bypass via NoopAuthenticationFunc Default

Updated under an hour ago (2026-10-19 06:10 UTC)

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It affects getkin kin-openapi. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for getkin kin-openapi

Exploited in the last 30 days

kin-openapi is a Go project for handling OpenAPI files. Prior to 0.144.0, ValidationHandler.Load() in openapi3filter/validation_handler.go silently replaces a nil AuthenticationFunc with NoopAuthenticationFunc, which returns nil without checking credentials. This substitution causes every OpenAPI security requirement to be satisfied for unauthenticated requests when an application relies on ValidationHandler as its enforcement middleware. The no-op callback prevents the fail-closed ErrAuthenticationServiceMissing path from being reached and forwards the request to protected handlers that may require an API key, OAuth token, or another security scheme. This issue is fixed in version 0.144.0.

CVSS: 9.1 CRITICAL (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Weakness (CWE): CWE-287
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Aug 13, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

getkin kin-openapi getkin:kin_openapi (from the name)	before 0.144.0	CNA record

References

https://github.com/getkin/kin-openapi/security/advisories/GHSA-r277-6w6q-xmqwx-refsource-confirm
https://github.com/getkin/kin-openapi/commit/f0407d53b0730280266f454b755010e7eeb985dax-refsource-misc
https://github.com/getkin/kin-openapi/releases/tag/v0.144.0x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.