CVE-2026-31973

HIGH

NULL pointer dereference in samtools cram-size

Title source: cna
STIX 2.1

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.

Scores

CVSS v3 7.5
EPSS 0.0002
EPSS Percentile 5.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-476
Status published
Products (5)
samtools/samtools 1.23
samtools/samtools 1.17 - 1.21.1
samtools/samtools = 1.23
samtools/samtools >= 1.17, < 1.21.1
samtools/samtools >= 1.22, < 1.22.2
Published Mar 18, 2026
Tracked Since Mar 19, 2026