CVE-2025-30356: nasa cryptolib Integer Underflow (Wrap or Wraparound)

Vulnerability summary

CVE-2025-30356 is a critical (CVSS 9.8) Integer Underflow (Wrap or Wraparound) vulnerability in nasa cryptolib. EPSS estimates a 0.66% chance of exploitation in the next 30 days, higher than 50.8% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 01-04-2025
   PublishedVulnerability first disclosed.
2. 02-04-2025
   Last modifiedVulnerability information updated.

Description

CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. In 1.3.3 and earlier, a heap buffer overflow vulnerability persists in the Crypto_TC_ApplySecurity function due to an incomplete validation check on the fl (frame length) field. Although CVE-2025-29912 addressed an underflow issue involving fl, the patch fails to fully prevent unsafe calculations. As a result, an attacker can still craft malicious frames that cause a negative tf_payload_len, which is then interpreted as a large unsigned value, leading to a heap buffer overflow in a memcpy call.

• 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-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.