{"id":"CVE-2026-116742","published":"2026-10-26T22:16:58.680","lastModified":"2026-10-26T22:16:58.680","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.","cvssScore":4.4,"cvssSeverity":"MEDIUM","cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L","cwes":["CWE-197"],"vendors":[],"products":[],"references":[{"url":"https://github.com/samtools/htslib","tags":[]},{"url":"https://github.com/samtools/htslib/blob/1.24/bgzf.c#L2504","tags":[]},{"url":"https://github.com/samtools/htslib/commit/18dddf02bb2c0053b32acec427723555a24b2873","tags":[]},{"url":"https://github.com/samtools/htslib/issues/2113","tags":[]},{"url":"https://github.com/samtools/htslib/pull/2057","tags":[]},{"url":"https://hackmd.io/@haindpwn/htslib-bgzf-gzi-int-truncation-oob","tags":[]},{"url":"https://www.vulncheck.com/advisories/htslib-through-1.24-heap-out-of-bounds-write-via-truncated-gzi-index-count","tags":[]}],"exploitRefs":[{"url":"https://github.com/samtools/htslib","tags":[]},{"url":"https://github.com/samtools/htslib/blob/1.24/bgzf.c#L2504","tags":[]},{"url":"https://github.com/samtools/htslib/commit/18dddf02bb2c0053b32acec427723555a24b2873","tags":[]},{"url":"https://github.com/samtools/htslib/issues/2113","tags":[]},{"url":"https://github.com/samtools/htslib/pull/2057","tags":[]}],"hasPoc":true,"ai":null}