{"cve":"CVE-2026-41213","nvd":{"published":"2026-04-23T19:17:29.400","modified":"2026-10-26T21:10:00.170","status":"Analyzed","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_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","score":5.9},"cwes":["CWE-307","CWE-1289"],"references":["https://github.com/node-oauth/node-oauth2-server/security/advisories/GHSA-jhm7-29pj-4xvf","https://github.com/node-oauth/node-oauth2-server/security/advisories/GHSA-jhm7-29pj-4xvf"],"products":["node-oauth:node-oauth\\/oauth2-server"],"source":"nvd","synced_at":"2026-10-26T21:38:48.864438205+00:00"},"epss":{"cve":"CVE-2026-41213","score":0.00259,"percentile":0.17438,"date":"2026-10-26"},"kev":null,"osv":[{"id":"GHSA-jhm7-29pj-4xvf","url":"https://osv.dev/vulnerability/GHSA-jhm7-29pj-4xvf","summary":"@node-oauth/oauth2-server: PKCE code_verifier ABNF not enforced in token exchange allows brute-force redemption of intercepted authorization codes","modified":"2026-05-05T16:11:45.707781Z","packages":[{"ecosystem":"npm","name":"@node-oauth/oauth2-server","purl":"pkg:npm/%40node-oauth/oauth2-server","ranges":["<5.3.0"],"fixed":["5.3.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}