Cryptolib · Cryptolib · CVE-2026-21899
**Name of the Vulnerable Software and Affected Versions**
CryptoLib versions prior to 1.4.3
**Description**
CryptoLib is a software solution that uses the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft and a ground station. Prior to version 1.4.3, the `base64urlDecode` function contains a flaw where padding-stripping dereferences input data before verifying its validity. Specifically, it accesses `input[inputLen - 1]` before confirming that `inputLen` is greater than zero or that `input` is not NULL. If `inputLen` is zero, this results in an out-of-bounds read at `input[-1]`, potentially causing the process to crash. If `input` is NULL and `inputLen` is zero, a dereference of NULL - 1 occurs.
**Recommendations**
Versions prior to 1.4.3 should be updated to version 1.4.3 or later.