CVE-2026-31971

HIGH EPSS 25.4%
Published Mar 18, 20263mo ago · Modified Mar 19, 20263mo ago
7.1 CVSS 4.0
High
Find Similar
Published Mar 18, 2026 3mo ago
Last Modified Mar 19, 2026 3mo ago

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.

CVSS Details

Base Score
7.1
Exploitability
Impact
Vector string
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction P
Scope X

Threat Intelligence

EPSS Exploit Probability
25.4% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 4

CWE-121
CWE-122
CWE-1284
CWE-787 Out-of-bounds Write Memory Safety

Affected Products 3

VendorProductVersionRange
htslibhtslib* <1.21.1
htslibhtslib*≥1.22  –  <1.22.2
htslibhtslib1.23any

References 2

  • github.com https://github.com/samtools/htslib/commit/01cd003b46fa2ebea4d9be5475b11217eb4c11be
    Patch
  • github.com https://github.com/samtools/htslib/security/advisories/GHSA-jvx4-4wq7-6fmh
    PatchVendor Advisory

Remediation

  • github.com https://github.com/samtools/htslib/commit/01cd003b46fa2ebea4d9be5475b11217eb4c11be
    Patch
  • github.com https://github.com/samtools/htslib/security/advisories/GHSA-jvx4-4wq7-6fmh
    PatchVendor Advisory