{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-63850","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-07-19T07:54:57.016Z","datePublished":"2026-07-19T14:04:41.975Z","dateUpdated":"2026-08-05T12:36:28.456Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:36:28.456Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdgpu/vcn: set no_user_fence for VCN v5.0.0 enc ring\n\nVCN encoder and decoder rings do not support 64-bit user fence writes,\nreject CS submissions with user fences.\n\n(cherry picked from commit 49b1fbbb5a071197ee71e2d70959b1cb29bdc317)"}],"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 vulnerable code is reached via the local DRM_IOCTL_AMDGPU_CS ioctl on an AMDGPU render node (/dev/dri/renderD*), submitting a command buffer with AMDGPU_CHUNK_ID_FENCE to the VCN v5.0.0 encoder ring.\nAC:L - An attacker with render-node access can deterministically submit a VCN encoder CS with a user-fence chunk; no race, special memory layout, or non-default kernel configuration is required beyond having affected AMD VCN 5.0.0 hardware.\nPR:L - Exploitation requires access to the AMDGPU DRM render node, which is available to unprivileged local users in the render/video group (or equivalent GPU access), not root or capabilities obtainable only in the init namespace.\nUI:N - No victim interaction is needed beyond the attacker already having GPU render-node access; exploitation is fully attacker-driven through ioctl submission.\nS:U - Impact is kernel/GPU memory corruption and privilege escalation within the same host security boundary; it does not inherently cross a VM, container, or IOMMU isolation boundary.\nC:H - Submitting an unsupported 64-bit user fence causes the VCN hardware to perform misdirected GPU memory writes, providing a memory-corruption primitive that can be leveraged for arbitrary kernel memory disclosure.\nI:H - The malformed fence write gives the attacker a GPU-initiated arbitrary write primitive within the GPU virtual address space, enabling memory corruption and potential kernel code execution.\nA:H - Malformed VCN fence commands can hang the GPU, trigger kernel oopses, or crash the system when the unsupported fence operation is processed by hardware."}]}],"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_v5_0_0.c"],"versions":[{"version":"b6d1a06320519ac3bfda6ce81067a1bc409b9cff","lessThan":"9f5a1459ecc3195282be617639d710b54779c9dc","status":"affected","versionType":"git"},{"version":"b6d1a06320519ac3bfda6ce81067a1bc409b9cff","lessThan":"139a8a52ef4349c62129703b3a3e3a6ae4d634eb","status":"affected","versionType":"git"},{"version":"b6d1a06320519ac3bfda6ce81067a1bc409b9cff","lessThan":"2c350f3cd94be847ac216e1358ec7001eaaf0934","status":"affected","versionType":"git"},{"version":"b6d1a06320519ac3bfda6ce81067a1bc409b9cff","lessThan":"8cae0ce77de492d7c31c1532a2e80c0c6e7e58cb","status":"affected","versionType":"git"}]},{"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_v5_0_0.c"],"versions":[{"version":"6.9","status":"affected"},{"version":"0","lessThan":"6.9","status":"unaffected","versionType":"semver"},{"version":"6.12.91","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.33","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.0.10","lessThanOrEqual":"7.0.*","status":"unaffected","versionType":"semver"},{"version":"7.1","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":"6.9","versionEndExcluding":"6.12.91"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.9","versionEndExcluding":"6.18.33"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.9","versionEndExcluding":"7.0.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.9","versionEndExcluding":"7.1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/9f5a1459ecc3195282be617639d710b54779c9dc"},{"url":"https://git.kernel.org/stable/c/139a8a52ef4349c62129703b3a3e3a6ae4d634eb"},{"url":"https://git.kernel.org/stable/c/2c350f3cd94be847ac216e1358ec7001eaaf0934"},{"url":"https://git.kernel.org/stable/c/8cae0ce77de492d7c31c1532a2e80c0c6e7e58cb"}],"title":"drm/amdgpu/vcn: set no_user_fence for VCN v5.0.0 enc ring","x_generator":{"engine":"bippy-1.2.0"}}}}