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TI-2026-24517 Aliases CVE-2026-31973

NULL pointer dereference in samtools cram-size

Priority LOW 31CWE-476Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · Low · Low
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-476.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00555 46th percentileScored 2026-11-07
Fix Fixed samtools (samtools): 1.21.1, 1.22.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
samtoolssamtools1.17 to before 1.21.1; 1.22 to before 1.22.2; = 1.231.21.1, 1.22.2Patch availableCNA
  • samtools Vendorsamtools Affected 1.17 to before 1.21.1; 1.22 to before 1.22.2; = 1.23 Fixed in 1.21.1, 1.22.2 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:samtools:samtools:*:*:*:*:*:*:*:*1.17 – 1.21.1; 1.22 to before 1.22.2Vulnerablesamtools
cpe:2.3:a:samtools:samtools:1.23:*:*:*:*:*:*:*1.23Vulnerablesamtools
  • cpe:2.3:a:samtools:samtools:*:*:*:*:*:*:*:* Versions 1.17 – 1.21.1; 1.22 to before 1.22.2 Vulnerable ·samtools
  • cpe:2.3:a:samtools:samtools:1.23:*:*:*:*:*:*:* Versions 1.23 Vulnerable ·samtools

Remediation

  • Fix · CNA samtools (samtools) Fixed in 1.21.1, 1.22.2

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-31973
  2. 2026-10-23 EPSS moved to the 50th–90th percentile
  3. 2026-10-25 EPSS moved to the below the 50th percentile

References

Patch 1

Advisory 2

  • TI-2026-24516 samtools mpileup has use-after-free leading to an invalid read CVSS 4.0MEDIUM 6.9

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences