Findings

CVE-2026-31971

HTSlib is a library for reading and writing bioinformatics file formats.

Published Mar 18, 2026 · updated Jun 17, 2026 · htslib htslib

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 method, the 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.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Mar 18, 2026 · NIST NVD

    Detected

    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 method, the 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 bein

  2. Jun 17, 2026 · NIST NVD

    Updated

    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 method, the 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 bein

Affected

  • cpe htslib/htslibversion unspecified
  • cpe htslib/htslib1.23

Sources

  • CVE.orgVulnerability recordCVE-2026-31971

    Official CVE identifier

    cve.org
  • NIST NVDVulnerability recordCVE-2026-31971

    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 method, the `cram_byte_array_le

    nvd.nist.gov

References