{"id":"DEBIAN-CVE-2026-76844","details":"zlib 1.2.11 through 1.3.2 contains a heap buffer overflow: after an underlying write() fails, gz_write() returns without resetting strm.next_in, leaving it pointed at the caller's buffer. A later gz* write call then derives a position from the stale pointer and writes past a heap allocation; any write() failure reaches it, including EPIPE on a blocking descriptor, and in versions before 1.3.1.2 the failed write must be followed by a gzclearerr() call.","modified":"2026-11-07T11:00:09.601221772Z","published":"2026-08-24T14:17:02.250Z","upstream":["CVE-2026-76844"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-76844"}],"affected":[{"package":{"name":"zlib","ecosystem":"Debian:12","purl":"pkg:deb/debian/zlib?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:1.2.13.dfsg-1","1:1.2.13.dfsg-2","1:1.2.13.dfsg-3","1:1.3.dfsg+really1.3.1-1","1:1.3.dfsg+really1.3.1-2","1:1.3.dfsg+really1.3.1-3","1:1.3.dfsg+really1.3.2-1","1:1.3.dfsg+really1.3.2-2","1:1.3.dfsg+really1.3.2-3","1:1.3.dfsg+really1.3.2-4","1:1.3.dfsg-1","1:1.3.dfsg-2","1:1.3.dfsg-3","1:1.3.dfsg-3.1","1:1.3.dfsg-3.1~exp1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-76844.json"}},{"package":{"name":"zlib","ecosystem":"Debian:13","purl":"pkg:deb/debian/zlib?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:1.3.dfsg+really1.3.1-1+deb13u1"}]}],"versions":["1:1.3.dfsg+really1.3.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-76844.json"}},{"package":{"name":"zlib","ecosystem":"Debian:14","purl":"pkg:deb/debian/zlib?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:1.3.dfsg+really1.3.2-4"}]}],"versions":["1:1.3.dfsg+really1.3.1-1","1:1.3.dfsg+really1.3.1-2","1:1.3.dfsg+really1.3.1-3","1:1.3.dfsg+really1.3.2-1","1:1.3.dfsg+really1.3.2-2","1:1.3.dfsg+really1.3.2-3"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-76844.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H"}]}