Bug 2448860 (CVE-2026-31973)

Summary: CVE-2026-31973 samtools: SAMtools: Denial of Service due to NULL pointer dereference in cram-size command
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in SAMtools. In the `cram-size` command, a missing check for the return value of the `cram_decode_compression_header()` function can lead to a NULL pointer dereference. An attacker could exploit this by providing a specially crafted CRAM file. This vulnerability typically causes the program to crash, resulting in a Denial of Service (DoS).
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Description OSIDB Bzimport 2026-03-18 21:02:22 UTC
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.