{"id":"CVE-2026-116742","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-116742","generatedAt":"2026-10-28T01:53:31.070Z","title":"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.","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.","published":"2026-10-26T22:16:59.000Z","lastModified":"2026-10-27T16:04:23.000Z","status":"Deferred","sourceIdentifier":"disclosure@vulncheck.com","cvss":{"version":"4.0","score":4.8,"severity":"MEDIUM","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/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/M"},"cwe":["CWE-197"],"affected":[],"epss":null,"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and no EPSS score yet. Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-26T22:16:59.000Z","detail":{"score":"4.8","severity":"MEDIUM","publishedAt":"2026-10-26T22:16:58.680Z"},"summary":"New CVE, medium severity (CVSS 4.8)."}],"references":[{"url":"https://github.com/samtools/htslib","source":"disclosure@vulncheck.com"},{"url":"https://github.com/samtools/htslib/blob/1.24/bgzf.c#L2504","source":"disclosure@vulncheck.com"},{"url":"https://github.com/samtools/htslib/commit/18dddf02bb2c0053b32acec427723555a24b2873","source":"disclosure@vulncheck.com"},{"url":"https://github.com/samtools/htslib/issues/2113","source":"disclosure@vulncheck.com"},{"url":"https://github.com/samtools/htslib/pull/2057","source":"disclosure@vulncheck.com"},{"url":"https://hackmd.io/@haindpwn/htslib-bgzf-gzi-int-truncation-oob","source":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/htslib-through-1.24-heap-out-of-bounds-write-via-truncated-gzi-index-count","source":"disclosure@vulncheck.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-116742","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}