CVE-2026-9495

MEDIUM EPSS 27.9%
Published May 26, 20261mo ago · Modified Jun 17, 20261w ago
5.5 CVSS 4.0
Medium
Find Similar
Published May 26, 2026 1mo ago
Last Modified Jun 17, 2026 1w ago

Description

Versions of the package @koa/router from 14.0.0 and before 15.0.0 are vulnerable to Access Control Bypass due to the middleware being silently dropped from the execution chain when the router prefix contains path parameters. Depending on what the skipped middleware was supposed to protect, an attacker could bypass authentication and authorization, evade rate limiting or bypass input sanitization.

CVSS Details

Base Score
5.5
Exploitability
—
Impact
—
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
27.9% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-284

References 4

  • github.com https://github.com/koajs/router/commit/d53e17f284557b1f417946f9807ee52290c3c759
  • github.com https://github.com/koajs/router/issues/202
  • github.com https://github.com/koajs/router/pull/206
  • security.snyk.io https://security.snyk.io/vuln/SNYK-JS-KOAROUTER-12215044

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.