CVE-2026-116742

Description

HTSlib through 1.24 contains a heap out-of-bounds write and read vulnerability in bgzf_index_load_hfile() in bgzf.c that allows attackers to corrupt heap memory by supplying a crafted .gzi index entry count. A count of 0xFFFFFFFF truncates noffs to zero, causing writes past a malloc(0) buffer and an offs[-1] read in bgzf_useek(), resulting in heap corruption or crashes in tools like samtools and bcftools.

References

https://www.vulncheck.com/advisories/htslib-through-1.24-heap-out-of-bounds-write-via-truncated-gzi-index-count

https://hackmd.io/@haindpwn/htslib-bgzf-gzi-int-truncation-oob

https://github.com/samtools/htslib/pull/2057

https://github.com/samtools/htslib/issues/2113

https://github.com/samtools/htslib/commit/18dddf02bb2c0053b32acec427723555a24b2873

https://github.com/samtools/htslib/blob/1.24/bgzf.c#L2504

https://github.com/samtools/htslib

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-110490

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3

CVSS v4

EPSS