Vulnerability Description
@node-oauth/oauth2-server is a module for implementing an OAuth2 server in Node.js. The token exchange path accepts RFC7636-invalid code_verifier values (including one-character strings) for S256 PKCE flows. Because short/weak verifiers are accepted and failed verifier attempts do not consume the authorization code, an attacker who intercepts an authorization code can brute-force code_verifier guesses online until token issuance succeeds.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Node-Oauth | Node-Oauth\/Oauth2-Server | < 5.3.0 |
Related Weaknesses (CWE)
References
- https://github.com/node-oauth/node-oauth2-server/security/advisories/GHSA-jhm7-2ExploitMitigationVendor Advisory
- https://github.com/node-oauth/node-oauth2-server/security/advisories/GHSA-jhm7-2ExploitMitigationVendor Advisory
FAQ
What is CVE-2026-41213?
CVE-2026-41213 is a vulnerability with a CVSS score of 5.9 (MEDIUM). @node-oauth/oauth2-server is a module for implementing an OAuth2 server in Node.js. The token exchange path accepts RFC7636-invalid code_verifier values (including one-character strings) for S256 PKCE...
How severe is CVE-2026-41213?
CVE-2026-41213 has been rated MEDIUM with a CVSS base score of 5.9/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-41213?
Check the references section above for vendor advisories and patch information. Affected products include: Node-Oauth Node-Oauth\/Oauth2-Server.