CVE-2026-28699: Gitea: OAuth2 access token scope enforcement bypass via HTTP Basic authentication

Summary Gitea fails to enforce OAuth2 access token scopes when the token is submitted via HTTP Basic authentication instead of a Bearer token. An OAuth2 application granted only read:user can use the same token as Autho…

8.1CVSS Score

HIGHSeverity

NOCISA KEV

VulnerabilityImpact Type

📋 Vulnerability Details

CVE ID	CVE-2026-28699
Vendor	go
Affected Product	code.gitea.io/gitea
Vulnerability Type	Vulnerability
CVSS Score	8.1 (HIGH)
Actively Exploited	❌ No known exploitation
Patch Status	See Vendor Advisory →
Reported By	CYBERDUDEBIVASH SENTINEL APEX Intelligence (via github_advisories)

🔬 Technical Analysis

Summary Gitea fails to enforce OAuth2 access token scopes when the token is submitted via HTTP Basic authentication instead of a Bearer token. An OAuth2 application granted only `read:user` can use the same token as `Authorization: Basic base64( :x-oauth-basic)` and perform write actions, including modifying profiles, adding email addresses, creating repositories, and deleting repositories as the authorizing user.

Details Root cause: `services/auth/basic.go` accepts OAuth2 access tokens through the Basic auth path but does not store the token scope in the request context: ```go`

// services/auth/basic.go if uid != 0 { store.GetData()["LoginMethod"] = OAuth2TokenMethodName store.GetData()["IsApiToken"] = true // scope is NOT set return u, nil } `` The scope enforcement middlewar

📚 Advisory References

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