CVE-2023-44378: consensys gnark Integer Underflow (Wrap or Wraparound)

Vulnerability summary

CVE-2023-44378 is a high (CVSS 7.1) Integer Underflow (Wrap or Wraparound) vulnerability in consensys gnark. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 13.4% of scored vulnerabilities.

Timeline

1. 09-10-2023
   PublishedVulnerability first disclosed.
2. 19-09-2024
   Last modifiedVulnerability information updated.

Description

gnark is a zk-SNARK library that offers a high-level API to design circuits. Prior to version 0.9.0, for some in-circuit values, it is possible to construct two valid decomposition to bits. In addition to the canonical decomposition of `a`, for small values there exists a second decomposition for `a+r` (where `r` is the modulus the values are being reduced by). The second decomposition was possible due to overflowing the field where the values are defined. Upgrading to version 0.9.0 should fix the issue without needing to change the calls to value comparison methods.

• CWE-191Integer Underflow (Wrap or Wraparound)The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.
• CWE-697Incorrect ComparisonThe product compares two entities in a security-relevant context, but the comparison is incorrect.