CVE-2023-39363

Description

Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). In versions 0.2.15, 0.2.16 and 0.3.0, named re-entrancy locks are allocated incorrectly. Each function using a named re-entrancy lock gets a unique lock regardless of the key, allowing cross-function re-entrancy in contracts compiled with the susceptible versions. A specific set of conditions is required to result in misbehavior of affected contracts, specifically: a `.vy` contract compiled with `vyper` versions `0.2.15`, `0.2.16`, or `0.3.0`; a primary function that utilizes the `@nonreentrant` decorator with a specific `key` and does not strictly follow the check-effects-interaction pattern (i.e. contains an external call to an untrusted party before storage updates); and a secondary function that utilizes the same `key` and would be affected by the improper state caused by the primary function. Version 0.3.1 contains a fix for this issue.

Weakness classification

• security-advisories@github.com: CWE-863

Primary references

• security-advisories@github.com — Patch
• security-advisories@github.com — Patch
• security-advisories@github.com — Exploit, Patch, Third Party Advisory
• security-advisories@github.com — Exploit, Third Party Advisory
• security-advisories@github.com — Exploit, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Patch
• af854a3a-2127-422b-91ae-364da2661108 — Patch
• af854a3a-2127-422b-91ae-364da2661108 — Exploit, Patch, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Exploit, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Exploit, Third Party Advisory