{"cve":"CVE-2026-120263","nvd":{"published":"2026-11-01T10:18:37.520","modified":"2026-11-01T10:18:37.637","status":"Deferred","description":"When `[oauth2_client].ACCOUNT_LINKING` is set to `auto` (not the default) and registration is enabled, the link-account sign-up form looked up the existing account to link by the user name or email submitted in the form instead of the identity asserted by the OAuth2 provider. An attacker with an account on a configured OAuth2 provider could submit another user's name, link their external identity to that Gitea account and be signed in as it without its password, including as an administrator. The link persisted for later sign-ins. Automatic linking now only happens when the existing account matches the provider's email or provider-derived user name; otherwise the account password is required.","cvss_v4":null,"cvss_v3":null,"cwes":["CWE-287","CWE-639"],"references":["https://blog.gitea.com/release-of-28.3.0/","https://github.com/go-gitea/gitea/pull/40121","https://github.com/go-gitea/gitea/pull/40137","https://github.com/go-gitea/gitea/releases/tag/v28.3.0","https://github.com/go-gitea/gitea/security/advisories/GHSA-8p3x-w464-4g6v"],"reference_tags":[{"url":"https://blog.gitea.com/release-of-28.3.0/","tags":[]},{"url":"https://github.com/go-gitea/gitea/pull/40121","tags":[]},{"url":"https://github.com/go-gitea/gitea/pull/40137","tags":[]},{"url":"https://github.com/go-gitea/gitea/releases/tag/v28.3.0","tags":[]},{"url":"https://github.com/go-gitea/gitea/security/advisories/GHSA-8p3x-w464-4g6v","tags":[]}],"products":[],"affected":[],"source":"nvd","synced_at":"2026-11-01T10:34:16.358491727+00:00"},"epss":{"cve":"CVE-2026-120263","score":0.00198,"percentile":0.09603,"date":"2026-11-01"},"kev":null,"exploits":[],"weaknesses":[{"name":"Improper Authentication","common_name":null,"deprecated":false,"replaced_by":[],"id":"CWE-287"},{"name":"Authorization Bypass Through User-Controlled Key","common_name":null,"deprecated":false,"replaced_by":[],"id":"CWE-639"}],"osv":[],"fixed":[],"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.","Public exploits: links to the Exploit Database (https://www.exploit-db.com, by OffSec; index under GPL-2.0), Rapid7's Metasploit Framework modules (https://github.com/rapid7/metasploit-framework, BSD-3-Clause) and ProjectDiscovery's nuclei templates (https://github.com/projectdiscovery/nuclei-templates, MIT). Only the links, titles and dates are stored; no exploit code is fetched or served.","CWE names and descriptions: MITRE's Common Weakness Enumeration (https://cwe.mitre.org), Copyright © 2006–2026, The MITRE Corporation, under the CWE terms of use (https://cwe.mitre.org/about/termsofuse.html). CWE is a trademark of The MITRE Corporation."]}