{"id":"DEBIAN-CVE-2026-66038","details":"FFmpeg through 8.1.2, fixed in commit 8670835, contains an information disclosure vulnerability in the LCL/ZLIB video decoder that allows attackers to expose uninitialized heap memory by supplying a valid zlib stream that inflates to fewer bytes than the expected frame size. The zlib_decomp() function in lcldec.c treats short decompression as non-fatal and continues to the RGB24 conversion path, which copies a full frame's worth of rows from the allocation buffer using original frame dimensions, causing uninitialized heap contents including pointer-derived allocator bytes to be copied into the attacker-observable AVFrame output and potentially defeating ASLR in long-lived media processing services.","modified":"2026-09-01T16:06:56.744208034Z","published":"2026-07-24T20:18:20.727Z","upstream":["CVE-2026-66038"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-66038"}],"affected":[{"package":{"name":"ffmpeg","ecosystem":"Debian:12","purl":"pkg:deb/debian/ffmpeg?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7:5.1.3-1","7:5.1.3-2","7:5.1.4-0+deb12u1","7:5.1.5-0+deb12u1","7:5.1.6-0+deb12u1","7:5.1.7-0+deb12u1","7:5.1.8-0+deb12u1","7:5.1.9-0+deb12u1","7:6.0-1","7:6.0-2","7:6.0-3","7:6.0-4","7:6.0-5","7:6.0-6","7:6.0-7","7:6.0-8","7:6.0-9","7:6.1-1","7:6.1-2","7:6.1-3","7:6.1-4","7:6.1-5","7:6.1.1-1","7:6.1.1-2","7:6.1.1-3","7:6.1.1-4","7:6.1.1-5","7:7.0-1","7:7.0.1-1","7:7.0.1-2","7:7.0.1-3","7:7.0.1-4","7:7.0.1-5","7:7.0.2-1","7:7.0.2-2","7:7.0.2-3","7:7.1-1","7:7.1-2","7:7.1-3","7:7.1-4","7:7.1.1-1","7:7.1.2-1","7:7.1.3-1","7:8.0-1","7:8.0-2","7:8.0.1-1","7:8.0.1-2","7:8.0.1-3","7:8.1-1","7:8.1-2","7:8.1-3","7:8.1.1-1","7:8.1.1-2","7:8.1.1-3","7:8.1.1-4","7:8.1.2-1","7:8.1.2-2","7:9.0-1","7:9.0.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-66038.json"}},{"package":{"name":"ffmpeg","ecosystem":"Debian:13","purl":"pkg:deb/debian/ffmpeg?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7:7.1.1-1","7:7.1.2-0+deb13u1","7:7.1.2-1","7:7.1.3-0+deb13u1","7:7.1.3-1","7:7.1.4-0+deb13u1","7:7.1.5-0+deb13u1","7:8.0-1","7:8.0-2","7:8.0.1-1","7:8.0.1-2","7:8.0.1-3","7:8.1-1","7:8.1-2","7:8.1-3","7:8.1.1-1","7:8.1.1-2","7:8.1.1-3","7:8.1.1-4","7:8.1.2-1","7:8.1.2-2","7:9.0-1","7:9.0.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-66038.json"}},{"package":{"name":"ffmpeg","ecosystem":"Debian:14","purl":"pkg:deb/debian/ffmpeg?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7:7.1.1-1","7:7.1.2-1","7:7.1.3-1","7:8.0-1","7:8.0-2","7:8.0.1-1","7:8.0.1-2","7:8.0.1-3","7:8.1-1","7:8.1-2","7:8.1-3","7:8.1.1-1","7:8.1.1-2","7:8.1.1-3","7:8.1.1-4","7:8.1.2-1","7:8.1.2-2","7:9.0-1","7:9.0.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-66038.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"}]}