{"id":"CVE-2026-51807","details":"Heap-based out-of-bounds write in j2k_precinct_subband::parse_packet_header() in OpenHTJ2K versions 0.18.3 and earlier (fixed in v0.18.4) caused by missing bounds validation before coding-pass lengths are written to j2k_codeblock::pass_length[128]. A crafted JPEG 2000 codestream containing malformed PPM packet headers can trigger a heap-based out-of-bounds write in j2k_precinct_subband::parse_packet_header() in source/core/coding/coding_units.cpp due to missing bounds validation for the j2k_codeblock::pass_length[128] array which can lead to heap corruption and process termination.","modified":"2026-08-12T03:51:48.919784133Z","published":"2026-07-14T00:00:00Z","database_specific":{"cna_assigner":"mitre","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/51xxx/CVE-2026-51807.json"},"references":[{"type":"WEB","url":"https://github.com/osamu620/OpenHTJ2K/blob/main/CHANGELOG"},{"type":"WEB","url":"https://github.com/osamu620/OpenHTJ2K/compare/0778b93...v0.18.4"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/51xxx/CVE-2026-51807.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-51807"},{"type":"FIX","url":"https://github.com/osamu620/OpenHTJ2K/commit/0778b93"},{"type":"PACKAGE","url":"https://github.com/osamu620/OpenHTJ2K/releases"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/osamu620/openhtj2k","events":[{"introduced":"0"},{"fixed":"0778b93"}],"database_specific":{"source":"REFERENCES"}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-51807.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}