CVE-2026-31973
Severity CVSS v4.0:
MEDIUM
Type:
CWE-476
NULL Pointer Dereference
Publication date:
18/03/2026
Last modified:
19/03/2026
Description
SAMtools is a program for reading, manipulating and writing bioinformatics file formats. Starting in version 1.17, in the cram-size command, used to write information about how well CRAM files are compressed, a check to see if the `cram_decode_compression_header()` was missing. If the function returned an error, this could lead to a NULL pointer dereference. Exploiting this bug causes a NULL pointer dereference. Typically this will cause the program to crash. Versions 1.23.1, 1.22.2 and 1.21.1 include fixes for this issue. There is no workaround for this issue.
Impact
Base Score 4.0
6.90
Severity 4.0
MEDIUM
Base Score 3.x
7.50
Severity 3.x
HIGH
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:a:samtools:samtools:*:*:*:*:*:*:*:* | 1.17 (including) | 1.21.1 (including) |
| cpe:2.3:a:samtools:samtools:*:*:*:*:*:*:*:* | 1.22 (including) | 1.22.2 (excluding) |
| cpe:2.3:a:samtools:samtools:1.23:*:*:*:*:*:*:* |
To consult the complete list of CPE names with products and versions, see this page



