{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89818","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.768Z","datePublished":"2026-09-16T10:30:50.946Z","dateUpdated":"2026-09-16T14:38:59.776Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-16T14:38:59.776Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdgpu/vcn: fix integer overflow in dec_msg buffer count check\n\nIf the supplied msg[2] (num_buffers) is 0x3FFFFFFF, the expression\n6 + num_buffers * 4 wraps to 2 and the bounds check passes, letting\nthe parser loop far past the end of the message BO. Triggering it\nadditionally requires a ~4GiB mapping so that msg[1] survives the\nearlier \"header does not fit in BO\" check.\n\nRewrite the test in division form, which is overflow-free by\nconstruction. Also update the message to reflect that msg is invalid."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","baseScore":7.1,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The bug is reached only via the local DRM_IOCTL_AMDGPU_CS ioctl on /dev/dri/renderD* (amdgpu_cs_ioctl → amdgpu_cs_patch_jobs → amdgpu_cs_patch_ibs → vcn_v3/v4_0_ring_patch_cs_in_place → vcn_*_dec_msg). There is no network or physical path to the VCN decode-message parser.\nAC:L - The attacker fully controls the decode-message GEM BO. Setting num_buffers to 0x3FFFFFFF with a ~4GiB mapping makes 6+num_buffers*4 wrap to 2 so the uint32 bounds check passes deterministically; allocating that mapping is attacker-controlled on typical GPU workstations and cloud GPU hosts.\nPR:L - AMDGPU_CS is registered with DRM_AUTH|DRM_RENDER_ALLOW, so any unprivileged local user who can open the AMDGPU render node (typical render/video group on desktops, handhelds, Android, and GPU cloud instances) can submit VCN command buffers without root.\nUI:N - The attacker submits the crafted VCN command buffer through their own DRM context; no separate victim action such as opening a file or mounting a filesystem is required.\nS:U - The out-of-bounds read is performed by the CPU in the kernel kmap of the message BO and stays within the kernel security authority; it is not a VM escape or IOMMU/DMA boundary bypass.\nC:H - Bypassing the buffer-count check lets the parser loop about 0x3FFFFFFF times, each step reading 16 bytes past the kmapped BO, an unbounded kernel out-of-bounds read well beyond a few bytes.\nI:N - The loop only reads message dwords and, when a CREATE record is seen, still bounds-checks offset/size against the BO before any further access; no out-of-bounds write or control-flow hijack primitive is produced.\nA:H - The unbounded walk past the kmapped BO into unmapped kernel or MMIO address space causes a page fault/oops, and the billion-iteration loop can also soft-lock the CS path before faulting."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c","drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c"],"versions":[{"version":"88411caee8f576d6b5abf6531232fcc0ce756dc5","lessThan":"c2340281be4ddacb8c203e2bce59b126d1d6c4c8","status":"affected","versionType":"git"},{"version":"c72a8b4dc6d598e3831ef3abd9c6527dfbf4810e","lessThan":"6dceaeceaa7c8396339f3ea34b0110cb912ca61b","status":"affected","versionType":"git"},{"version":"7688143ca62edeecacb3ba0a2cea129dbd262a18","lessThan":"47799e1f893d47d8af231710a61065e3ec8a13e8","status":"affected","versionType":"git"},{"version":"63b51e8a9d54317d31cc3856c1e12407070d5fc2","lessThan":"7e28853c78c20bb8ba4c1dba702430cd05e09f76","status":"affected","versionType":"git"},{"version":"b193019860d61e92da395eae2011f2f6716b182f","lessThan":"9ae19bd60891bea0a7b7504cc8dbfe74570ac3b3","status":"affected","versionType":"git"},{"version":"b193019860d61e92da395eae2011f2f6716b182f","lessThan":"4d7390530853eb7befda9cc786e4c86e8ad7ac9e","status":"affected","versionType":"git"},{"version":"f55552adb100eb54a6e6dabff4fbdc8679bd3fa0","status":"affected","versionType":"git"},{"version":"82c535eff05490c71153af57de9fe85502fcb5d5","status":"affected","versionType":"git"},{"version":"638d3e0b9eb77aa53fdd60e2b928761d16ba76fa","status":"affected","versionType":"git"},{"version":"870c8738c3774336baedddd0240951d078a703b8","status":"affected","versionType":"git"},{"version":"638e48ee39d0f2af9336f917a6f5d6692dd64d93","status":"affected","versionType":"git"},{"version":"e382e0b81a3e7bd21504fee1d01ae8b08f84d3a7","status":"affected","versionType":"git"},{"version":"3c817a60b09eaab926e475088e750936efcc95ae","status":"affected","versionType":"git"},{"version":"6.1.175","lessThan":"6.1.188","status":"affected","versionType":"semver"},{"version":"6.6.140","lessThan":"6.6.157","status":"affected","versionType":"semver"},{"version":"6.12.90","lessThan":"6.12.110","status":"affected","versionType":"semver"},{"version":"6.18.32","lessThan":"6.18.51","status":"affected","versionType":"semver"},{"version":"5.15.209","lessThan":"5.16","status":"affected","versionType":"semver"},{"version":"7.0.9","lessThan":"7.1","status":"affected","versionType":"semver"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c","drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c"],"versions":[{"version":"7.1","status":"affected"},{"version":"0","lessThan":"7.1","status":"unaffected","versionType":"semver"},{"version":"6.1.188","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.157","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.110","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.51","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.5","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.175","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.140","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12.90","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18.32","versionEndExcluding":"6.18.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.1","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.1","versionEndExcluding":"7.3-rc1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.209"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.0.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.0.9"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/c2340281be4ddacb8c203e2bce59b126d1d6c4c8"},{"url":"https://git.kernel.org/stable/c/6dceaeceaa7c8396339f3ea34b0110cb912ca61b"},{"url":"https://git.kernel.org/stable/c/47799e1f893d47d8af231710a61065e3ec8a13e8"},{"url":"https://git.kernel.org/stable/c/7e28853c78c20bb8ba4c1dba702430cd05e09f76"},{"url":"https://git.kernel.org/stable/c/9ae19bd60891bea0a7b7504cc8dbfe74570ac3b3"},{"url":"https://git.kernel.org/stable/c/4d7390530853eb7befda9cc786e4c86e8ad7ac9e"}],"title":"drm/amdgpu/vcn: fix integer overflow in dec_msg buffer count check","x_generator":{"engine":"bippy-1.2.0"}}}}