CVE-2026-103090 Unauthenticated Biscuit Credential Disclosure via GET /enroll/status in Google OSS Agent Mesh (SAM)
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-103090?
CVE-2026-103090 is a high-severity vulnerability in Google SAM, published on 21 Oct 2026.
Official description
Missing Authentication for Critical Function (CWE-306) and Insufficiently Protected Credentials (CWE-522) in the control plane enrollment status handler (HandleEnrollStatus at GET /enroll/status in internal/controlplane/server.go) in Google OSS Agent Mesh (SAM) versions 0.1.0-alpha.1 through 0.1.0-alpha.8 allow an unauthenticated remote attacker to retrieve an approved bootstrap-enrolled peer's signed Biscuit identity token by supplying a peer_id obtainable from the unauthenticated GET /info endpoint. A related flaw in POST /enroll allowed any bootstrap-token holder to re-fetch another peer's credential. An attacker can replay the disclosed Biscuit token as a bearer credential on /policies to read mesh authorization policies and on /routers/lease to overwrite advertised router multiaddrs. Users should upgrade to version 0.1.0-alpha.9 or later, which requires cryptographic proof of possession of the enrollment private key on credential-releasing endpoints, enforces rate limiting, and validates router lease addresses.
Which versions are affected by CVE-2026-103090?
How do I fix CVE-2026-103090?
No fix has been published for CVE-2026-103090 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-103090 being exploited?
There is no known exploitation of CVE-2026-103090 in the wild and no public exploit code.
Sources
Also known as GHSA-hp3x-79wr-rx66, GHSA-xhg2-hv24-f4rp.