Vulnerability · Published Aug 5, 2024 · Assigned by GitHub_M
CVE-2024-42350Public key confusion in third party block in Biscuit
Low 3.0
In plain English
A low-severity security flaw in biscuit from biscuit-auth. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities).
Official description
Biscuit is an authorization token with decentralized verification, offline attenuation and strong security policy enforcement based on a logic language. Third-party blocks can be generated without transferring the whole token to the third-party authority. Instead, a `ThirdPartyBlock` request can be sent, providing only the necessary info to generate a third-party block and to sign it: 1. the public key of the previous block (used in the signature), 2. the public keys part of the token symbol table (for public key interning in datalog expressions). A third-part block request forged by a malicious user can trick the third-party authority into generating datalog trusting the wrong keypair. Tokens with third-party blocks containing `trusted` annotations generated through a third party block request. This has been addressed in version 4 of the specification. Users are advised to update their implementations to conform. There are no known workarounds for this vulnerability.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| biscuit-auth | biscuit | < 4 |
Weakness: CWE-668 · Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:N/I:L/A:N