{"schema":"threatline.record/2","record":{"id":"CVE-2026-99063","aliases":[],"summary":"dm ioctl: don't let data_start run past the buffer","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ndm ioctl: don't let data_start run past the buffer\n\nstruct dm_ioctl has seven bytes of trailing padding, so the smallest\nbuffer userspace is allowed to ask for, offsetof(struct dm_ioctl, data),\nis seven bytes shorter than sizeof(struct dm_ioctl).\n\nget_result_buffer() sets data_start to sizeof(struct dm_ioctl) without\nlooking at how big the buffer actually is. Ask for the minimum and\ndata_start ends up seven bytes past the end. Callers add it to\ndata_size, and ctl_ioctl() copies that much back to userspace:\n\n  BUG: KASAN: slab-out-of-bounds in _copy_to_user+0xad/0xd0\n  Read of size 312 at addr ffff8880169e4c00 by task repro-dm/140\n   ctl_ioctl+0x5e3/0xcb0\n   dm_ctl_ioctl+0x25/0x40\n  allocated 305-byte region [ffff8880169e4c00, ffff8880169e4d31)\n\nA DM_LIST_DEVICES with data_size set to 305 is enough to hit it, and the\nseven bytes that leak are whatever sat next to the allocation.\n\nClamp data_start to the buffer size.\n\nNote that this is not a security bug because the out-of-bounds read can\nonly be triggered by root.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99063","source_modified_at":"2026-10-23T12:23:04.655Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Linux","vendor":"Linux","versions":[{"version":"76c072b48e39e9291fbf02d6c912cf27d65e093d","lessThan":"98195e822343a656b92e235847ab3e72b1a3f920","status":"affected","versionType":"git"},{"version":"76c072b48e39e9291fbf02d6c912cf27d65e093d","lessThan":"e5c3f3d8935ecc64c962fb66e6a86dbf79218f61","status":"affected","versionType":"git"},{"version":"76c072b48e39e9291fbf02d6c912cf27d65e093d","lessThan":"5680b6fb3054677d4ee65d3baba24b649f1b430e","status":"affected","versionType":"git"},{"version":"76c072b48e39e9291fbf02d6c912cf27d65e093d","lessThan":"725b49c689bbb29ef740b0d6b5ea9390baa9a695","status":"affected","versionType":"git"},{"version":"76c072b48e39e9291fbf02d6c912cf27d65e093d","lessThan":"9b3fcf519d370df94a56f3b272d9eddffffa5be8","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99063","source_modified_at":"2026-10-23T12:23:04.655Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Linux","vendor":"Linux","versions":[{"version":"2.6.25","status":"affected"},{"version":"0","lessThan":"2.6.25","status":"unaffected","versionType":"semver"},{"version":"6.6.160","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.113","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.57","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.11","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99063","source_modified_at":"2026-10-23T12:23:04.655Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"98195e822343a656b92e235847ab3e72b1a3f920","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99063","source_modified_at":"2026-10-23T12:23:04.655Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"5680b6fb3054677d4ee65d3baba24b649f1b430e","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99063","source_modified_at":"2026-10-23T12:23:04.655Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"725b49c689bbb29ef740b0d6b5ea9390baa9a695","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99063","source_modified_at":"2026-10-23T12:23:04.655Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"9b3fcf519d370df94a56f3b272d9eddffffa5be8","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":null,"percentile":null,"score_date":null},"published_at":"2026-10-23T12:23:04.655Z","modified_at":"2026-10-23T12:23:04.655Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-99063","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23T12:23:04.655Z"}],"sources":["CVE List"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/98195e822343a656b92e235847ab3e72b1a3f920"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/e5c3f3d8935ecc64c962fb66e6a86dbf79218f61"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/5680b6fb3054677d4ee65d3baba24b649f1b430e"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/725b49c689bbb29ef740b0d6b5ea9390baa9a695"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/9b3fcf519d370df94a56f3b272d9eddffffa5be8"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-23T12:23:04.655Z","content_hash":"e42339da885f5f246060963e301d423e4bf6acdf1013689cb8133ef1b72a8dab"}}