Staging Environment: Content and features may be unstable or change without notice.
Advisory details: ubuntu_osv / UBUNTU-CVE-2026-31973
Advisory ID ubuntu_osv/UBUNTU-CVE-2026-31973
Aliases CVE-2026-31973
Summary 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.
Status Published
Exploitability 0.5
Weighted Severity 6.8
Risk 3.4
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (0)
There are no known CWE.
System Score Found at
cvssv3.1 7.5 https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-31973.json
cvssv4 6.9 https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-31973.json
ubuntu-priority medium https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-31973.json
Reference id Reference type URL
https://ubuntu.com/security/CVE-2026-31973
https://www.cve.org/CVERecord?id=CVE-2026-31973
http://www.openwall.com/lists/oss-security/2026/03/18/12
06fc2a219b3d7c94d3f412c09f6d1efd51199f2f Other https://github.com/samtools/samtools/commit/06fc2a219b3d7c94d3f412c09f6d1efd51199f2f
GHSA-x86f-q6fj-cm43 Other https://github.com/samtools/samtools/security/advisories/GHSA-x86f-q6fj-cm43
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Found at https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-31973.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N Found at https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-31973.json
Attack Vector (AV) Attack Complexity (AC) Attack Requirements (AT) Privileges Required (PR) User Interaction (UI) Vulnerable System Impact Confidentiality (VC) Vulnerable System Impact Integrity (VI) Vulnerable System Impact Availability (VA) Subsequent System Impact Confidentiality (SC) Subsequent System Impact Integrity (SI) Subsequent System Impact Availability (SA)

network

adjacent

local

physical

low

high

none

present

none

low

high

none

passive

active

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none

There are no SSVC decisions available.