{"id":"ALPINE-CVE-2025-59729","details":"When parsing the header for a DHAV file, there's an integer underflow in offset calculation that leads to reading the duration from before the start of the allocated buffer.\n\nIf we load a DHAV file that is larger than MAX_DURATION_BUFFER_SIZE bytes (0x100000) for example 0x101000 bytes, then at [0] we have size = 0x101000. At [1] we have end_buffer_size = 0x100000, and at [2] we have end_buffer_pos = 0x1000.\n\nThe loop then scans backwards through the buffer looking for the dhav tag; when it is found, we'll calculate end_pos based on a 32-bit offset read from the buffer.\n\nThere is subsequently a check [3] that end_pos is within the section of the file that has been copied into end_buffer, but it only correctly handles the cases where end_pos is before the start of the file or after the section copied into end_buffer, and not the case where end_pos is within the the file, but before the section copied into end_buffer. If we provide such an offset, (end_pos - end_buffer_pos) can underflow, resulting in the subsequent access at [4] occurring before the beginning of the allocation.\n\nWe recommend upgrading to version 8.0 or beyond.","modified":"2026-11-03T06:33:00.849610620Z","published":"2025-10-06T08:15:34.447Z","upstream":["CVE-2025-59729"],"references":[{"type":"ADVISORY","url":"https://security.alpinelinux.org/vuln/CVE-2025-59729"}],"affected":[{"package":{"name":"ffmpeg","ecosystem":"Alpine:v3.23","purl":"pkg:apk/alpine/ffmpeg?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.0-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2025-59729.json"}},{"package":{"name":"ffmpeg","ecosystem":"Alpine:v3.24","purl":"pkg:apk/alpine/ffmpeg?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.0-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2025-59729.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:P/VC:L/VI:H/VA:N/SC:L/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"}]}