CVE-2026-31973: Samtools Cram Decode Null Derefcve-2026-31973-samtools-cram-decode-null-deref
The return value of `cram_decode_compression_header()` is used without being checked for NULL. A malformed CRAM file may cause this function to return NULL, leading to a NULL pointer dereference when passed to other functions. Ensure the return value is checked before use.