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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-31971 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. When reading data encoded using the `BYTE_ARRAY_LEN` method, the `cram_byte_array_len_decode()` failed to validate that the amount of data being unpacked matched the size of the output buffer where it was to be stored. Depending on the data series being read, this could result either in a heap or a stack overflow with attacker-controlled bytes. 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 7.1 HIGH
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/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/01cd003b46fa2ebea4d9be5475b11217eb4c11be GitHub, Inc. Patch 
https://github.com/samtools/htslib/security/advisories/GHSA-jvx4-4wq7-6fmh 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-1284 Improper Validation of Specified Quantity in Input 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-2026-31971
NVD Published Date:
03/18/2026
NVD Last Modified:
03/19/2026
Source:
GitHub, Inc.