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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-31968 Detail

Description

HTSlib is a library for reading and writing bioinformatics file formats. CRAM is a compressed format which stores DNA sequence alignment data using a variety of encodings and compression methods. For the `VARINT` and `CONST` encodings, incomplete validation of the context in which the encodings were used could result in up to eight bytes being written beyond the end of a heap allocation, or up to eight bytes being written to the location of a one byte variable on the stack, possibly causing the values to adjacent variables to change unexpectedly. Depending on the data stream this could result either in a heap buffer overflow or a stack overflow. If a user opens a file crafted to exploit this issue it could lead to the program crashing, overwriting of data structures on the heap or stack in ways not expected by the program, or changing the control flow of the program. It may be possible to use this to obtain arbitrary code execution. Versions 1.23.1, 1.22.2 and 1.21.1 include fixes for this issue. There is no workaround for this issue.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 8.8 HIGH
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/samtools/htslib/commit/0ec436796eca7b4ce7fcc9b77270c102da29bb2e GitHub, Inc. Patch 
https://github.com/samtools/htslib/security/advisories/GHSA-cgcm-c9r2-p57j GitHub, Inc. Patch  Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-121 Stack-based Buffer Overflow GitHub, Inc.  
CWE-122 Heap-based Buffer Overflow GitHub, Inc.  
CWE-787 Out-of-bounds Write GitHub, Inc.  
CWE-843 Access of Resource Using Incompatible Type ('Type Confusion') GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-31968
NVD Published Date:
03/18/2026
NVD Last Modified:
03/19/2026
Source:
GitHub, Inc.