CVE-2026-31967

HTSlib is a library for reading and writing bioinformatics file formats. CRAM is a compressed format which stores DNA sequence alignment data. In the `cram_decode_slice()` function called while reading CRAM records, the value of the mate reference id field was not validated. Later use of this value, for example when converting the data to SAM format, could result in the out of bounds array reads when looking up the corresponding reference name. If the array value obtained also happened to be a valid pointer, it would be interpreted as a string and an attempt would be made to write the data as part of the SAM record. This bug may allow information about program state to be leaked. It may also cause a program crash through an attempt to access invalid memory. Versions 1.23.1, 1.22.2 and 1.21.1 include fixes for this issue. There is no workaround for this issue.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/samtools/htslib/commit/9cefb46453ad471e933b8212d4f45920524d3357	Patch
https://github.com/samtools/htslib/security/advisories/GHSA-33x5-c6vj-8f2w	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:htslib:htslib::::::::
	cpe:2.3:a:htslib:htslib::::::::
	cpe:2.3:a:htslib:htslib:1.23:::::::*

History

No history.

Information

Published : 2026-03-18 20:16

Updated : 2026-03-19 14:36

NVD link : CVE-2026-31967

Mitre link : CVE-2026-31967

CVE.ORG link : CVE-2026-31967

JSON object : View

Products Affected

htslib

htslib

CWE

CWE-125

Out-of-bounds Read

CWE-129

Improper Validation of Array Index

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CRAM is a compressed format which stores DNA sequence alignment data. In the `cram_decode_slice()` function called while reading CRAM records, the value of the mate reference id field was not validated. Later use of this value, for example when converting the data to SAM format, could result in the out of bounds array reads when looking up the corresponding reference name. If the array value obtained also happened to be a valid pointer, it would be interpreted as a string and an attempt would be made to write the data as part of the SAM record. This bug may allow information about program state to be leaked. It may also cause a program crash through an attempt to access invalid memory. Versions 1.23.1, 1.22.2 and 1.21.1 include fixes for this issue. There is no workaround for this issue."}, {"lang": "es", "value": "HTSlib es una biblioteca para leer y escribir formatos de archivo bioinform\u00e1ticos. CRAM es un formato comprimido que almacena datos de alineaci\u00f3n de secuencias de ADN. En la funci\u00f3n 'cram_decode_slice()' llamada al leer registros CRAM, el valor del campo 'mate reference id' no fue validado. El uso posterior de este valor, por ejemplo al convertir los datos a formato SAM, podr\u00eda resultar en lecturas de array fuera de l\u00edmites al buscar el nombre de referencia correspondiente. Si el valor del array obtenido tambi\u00e9n resultara ser un puntero v\u00e1lido, ser\u00eda interpretado como una cadena y se intentar\u00eda escribir los datos como parte del registro SAM. Este error podr\u00eda permitir que se filtre informaci\u00f3n sobre el estado del programa. Tambi\u00e9n podr\u00eda causar un fallo del programa a trav\u00e9s de un intento de acceder a memoria inv\u00e1lida. Las versiones 1.23.1, 1.22.2 y 1.21.1 incluyen correcciones para este problema. 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