bbs-go through 4.4.6 contains an authentication bypass vulnerability in the /api/login/google_one_tap endpoint that allows remote attackers to log in as other users by submitting Google ID tokens issued to any OAuth client. Attackers operating their own Google OAuth client can capture a victim's Google-signed ID token and replay it, since the aud claim is never checked, to obtain an authenticated session as the victim's Google-linked account.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 1
- First seenCVSS 8.6NVD modified 2026-10-16 19:03
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 5
- https://github.com/mlogclub/bbs-go/blob/v4.4.6/internal/pkg/google/jwt.go#L55-L58
- https://github.com/mlogclub/bbs-go/blob/v4.4.6/internal/services/third_user_service.go#L274-L293
- https://hackmd.io/@hieuPenguinnn/bbs-go-google-one-tap-id-token-audience-confusion-account-takeover
- https://www.vulncheck.com/advisories/bbs-go-through-4.4.6-account-takeover-via-google-one-tap-login
- https://hackmd.io/@hieuPenguinnn/bbs-go-google-one-tap-id-token-audience-confusion-account-takeover