cve.bz

CVE-2026-9495

5.5 mediumEPSS 0.4%

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.

Severity

CVSS 4.0

5.5 medium
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

CVSS 3.1

7.3 high
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
EPSS
0.4% chance of exploitation in the next 30 days; higher than 29% of CVEs (scores of 2026-10-31)
CWE
CWE-284
Published
Modified
Record from
the NVD, synced

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-47p6-69vm-vw6vnpm@koa/router>=14.0.0 <15.0.015.0.0

References

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