SecuriTricks - CVE-2026-9495

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.

Product(s) Impacted

Vendor	Product	Versions
Koa	Router	14.0.0, <15.0.0

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-284

Improper Access Control

The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

*CPE(s)

Affected systems and software identified for this CVE.

Type	Vendor	Product	Version	Update	Edition	Language	Software Edition	Target Software	Target Hardware	Other Information
a	koa	router	14.0.0	/	/	/	/	/	/	/
a	koa	router	<15.0.0	/	/	/	/	/	/	/

References

https://github.com/koajs/router/commit/d53e17f284557b1f417946f9807ee52290c3c759

https://github.com/koajs/router/issues/202

https://github.com/koajs/router/pull/206

https://security.snyk.io/vuln/SNYK-JS-KOAROUTER-12215044

https://github.com/koajs/router/pull/206

CVSS Score

5.5 / 10

CVSS Data - 4.0

Attack Vector: NETWORK
Attack Complexity: LOW
Attack Requirements: NONE
Privileges Required: NONE
User Interaction: NONE
Scope:
Confidentiality Impact: LOW
Integrity Impact: LOW
Availability Impact: LOW
Exploit Maturity: PROOF_OF_CONCEPT

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

View Vector String

Timeline

Published: May 26, 2026, 7:16 a.m.
Last Modified: May 26, 2026, 8:16 p.m.

Status : Awaiting Analysis

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

[email protected]

CVE-2026-9495