{"id":"CVE-2026-97576","state":"PUBLISHED","title":"media: v4l2-ctrls: validate HEVC tile counts","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: v4l2-ctrls: validate HEVC tile counts\n\nThe stateless HEVC decoders read num_tile_columns_minus1 + 1 entries from\ncolumn_width_minus1[] and num_tile_rows_minus1 + 1 from row_height_minus1[]\nand use them as tile-loop bounds, but std_validate_compound() does not\nbound these u8 counts. Reject a V4L2_CTRL_TYPE_HEVC_PPS with tiling\nenabled whose tile counts exceed the uAPI array capacity, mirroring the\nexisting compound-control range checks.","publishedAt":"2026-09-25T10:21:59.298Z","updatedAt":"2026-10-19T09:09:38.813Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"9c0a718e24d4cd6d975f3df9740f968f62891a20","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"975e0180488966bb709092a52408604bd4f4edd9","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"724915535558b14c111ad8a498b896026dfe8d20","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"400cd78a63cc647412cf069c9851bdea2818340c","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"c7b1ef6dc57f4e57fe27cfdd3bf82033ed91ca34","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"ba1023d3a6d5d244d59f20c4ba6af4879ae08a9f","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"dc694a9929f7cb9c88ef91e45eb982b7bbe5a477","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/v4l2-core/v4l2-ctrls-core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.5","versionType":"semver"},{"version":"5.15.222","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.189","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.158","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.111","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.53","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/v4l2-core/v4l2-ctrls-core.c"]}],"references":["https://git.kernel.org/stable/c/9c0a718e24d4cd6d975f3df9740f968f62891a20","https://git.kernel.org/stable/c/975e0180488966bb709092a52408604bd4f4edd9","https://git.kernel.org/stable/c/724915535558b14c111ad8a498b896026dfe8d20","https://git.kernel.org/stable/c/400cd78a63cc647412cf069c9851bdea2818340c","https://git.kernel.org/stable/c/c7b1ef6dc57f4e57fe27cfdd3bf82033ed91ca34","https://git.kernel.org/stable/c/ba1023d3a6d5d244d59f20c4ba6af4879ae08a9f","https://git.kernel.org/stable/c/dc694a9929f7cb9c88ef91e45eb982b7bbe5a477"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/97xxx/CVE-2026-97576.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-97576","state":"PUBLISHED","datePublished":"2026-09-25T10:21:59.298Z","dateUpdated":"2026-10-19T09:09:38.813Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-24T16:01:01.156Z"},"containers":{"cna":{"title":"media: v4l2-ctrls: validate HEVC tile counts","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: v4l2-ctrls: validate HEVC tile counts\n\nThe stateless HEVC decoders read num_tile_columns_minus1 + 1 entries from\ncolumn_width_minus1[] and num_tile_rows_minus1 + 1 from row_height_minus1[]\nand use them as tile-loop bounds, but std_validate_compound() does not\nbound these u8 counts. Reject a V4L2_CTRL_TYPE_HEVC_PPS with tiling\nenabled whose tile counts exceed the uAPI array capacity, mirroring the\nexisting compound-control range checks."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"9c0a718e24d4cd6d975f3df9740f968f62891a20","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"975e0180488966bb709092a52408604bd4f4edd9","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"724915535558b14c111ad8a498b896026dfe8d20","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"400cd78a63cc647412cf069c9851bdea2818340c","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"c7b1ef6dc57f4e57fe27cfdd3bf82033ed91ca34","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"ba1023d3a6d5d244d59f20c4ba6af4879ae08a9f","versionType":"git"},{"version":"256fa3920874b0f1f4cb79ad6766493a22187153","status":"affected","lessThan":"dc694a9929f7cb9c88ef91e45eb982b7bbe5a477","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/v4l2-core/v4l2-ctrls-core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.5","versionType":"semver"},{"version":"5.15.222","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.189","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.158","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.111","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.53","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/v4l2-core/v4l2-ctrls-core.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/9c0a718e24d4cd6d975f3df9740f968f62891a20"},{"url":"https://git.kernel.org/stable/c/975e0180488966bb709092a52408604bd4f4edd9"},{"url":"https://git.kernel.org/stable/c/724915535558b14c111ad8a498b896026dfe8d20"},{"url":"https://git.kernel.org/stable/c/400cd78a63cc647412cf069c9851bdea2818340c"},{"url":"https://git.kernel.org/stable/c/c7b1ef6dc57f4e57fe27cfdd3bf82033ed91ca34"},{"url":"https://git.kernel.org/stable/c/ba1023d3a6d5d244d59f20c4ba6af4879ae08a9f"},{"url":"https://git.kernel.org/stable/c/dc694a9929f7cb9c88ef91e45eb982b7bbe5a477"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The attacker-controlled bytes are num_tile_columns_minus1, num_tile_rows_minus1 and column_width_minus1[]/row_height_minus1[] in struct v4l2_ctrl_hevc_pps, copied from userspace by VIDIOC_S_EXT_CTRLS through v4l_s_ext_ctrls → v4l2_s_ext_ctrls → user_to_new into std_validate_compound(); no network protocol carries those fields.\nAC:L - Setting V4L2_HEVC_PPS_FLAG_TILES_ENABLED with num_tile_columns_minus1>=20 or num_tile_rows_minus1>=22 is enough; the next decode job (hantro_g2_hevc_dec_run→prepare_tile_info_buffer, rkvdec assemble_hw_pps→compute_tiles_non_uniform, or cedrus_h265_setup→cedrus_h265_write_tiles) uses those u8 counts as loop bounds with no race or hardware-fault precondition.\nPR:L - rkvdec_open(), hantro_open() and cedrus_open() perform no capable() check; v4l2_open only requires opening the decoder /dev/videoN. On Rockchip, Allwinner and Hantro devices that node is granted to unprivileged video-group or Android media-client users, not init-namespace root.\nUI:N - The attacking process opens the HEVC decoder itself, issues VIDIOC_S_EXT_CTRLS with the crafted V4L2_CTRL_TYPE_HEVC_PPS, then QBUF/STREAMON via the request API. No separate victim mount, file-open, or playback action is required.\nS:U - The overflows remain in kernel stack (vdpu383 assemble_hw_pps column_width[22]), hantro tile_sizes DMA memory, and the rkvdec param_set PPS packet. This is kernel memory corruption under the same security authority, not a VM, IOMMU, or sandbox escape.\nC:H - cedrus_h265_write_tiles() and compute_tiles_non_uniform() index column_width_minus1[20] and row_height_minus1[22] with a u8 count up to 255, reading past the v4l2_ctrl_hevc_pps object into adjacent kernel heap that is then copied into stack and DMA tile buffers.\nI:H - compute_tiles_non_uniform() writes attacker-chosen column_width_minus1[i]+1 values past stack arrays column_width[20/22]; prepare_tile_info_buffer() writes up to 256x256 u16 pairs into a 20x22 tile_sizes DMA buffer; rkvdec_set_bw_field() stores COLUMN_WIDTH(i) past the 80-byte PPS packet.\nA:H - The stack smash of column_width/row_height, the tile_sizes DMA overflow, and rkvdec_set_bw_field() writes past param_set can walk into unmapped or poisoned memory and oops the kernel, and can wedge the HEVC decoder hardware. The trigger is repeatable at will."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:09:38.813Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.15.222"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.1.189"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.6.158"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.12.111"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.18.53"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"7.2.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}