{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-63844", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T07:54:57.015Z", "datePublished": "2026-07-19T14:04:38.452Z", "dateUpdated": "2026-08-05T12:36:21.992Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:36:21.992Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdgpu/jpeg: set no_user_fence for JPEG v4.0.3 ring\n\nJPEG rings do not support 64-bit user fence writes, reject CS\nsubmissions with user fences.\n\n(cherry picked from commit 2f6afc97d259d530f4f86c7743efbc573a8da927)" } ], "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 - Exploitation requires local access to the AMDGPU DRM render node and the DRM_IOCTL_AMDGPU_CS ioctl path; there is no network, adjacent-wireless, or physical-access entry point to the vulnerable JPEG ring submission code.\nAC:L - An attacker with render-node access can deterministically submit a command stream to the VCN JPEG ring with an AMDGPU_CHUNK_ID_FENCE user-fence chunk; no race or attacker-uncontrollable memory layout is required beyond having affected VCN 4.0.3 hardware.\nPR:L - The vulnerable amdgpu_cs_ioctl handler is gated by DRM_AUTH|DRM_RENDER_ALLOW, requiring a local unprivileged user with access to /dev/dri/renderD* (typically the render/video group), not root or capabilities obtainable only in the init namespace.\nUI:N - Once the attacker has render-node access, triggering the bug is fully programmatic via ioctl/GEM setup and does not require any additional victim interaction such as opening files or mounting filesystems.\nS:U - Impact is confined to the AMDGPU driver/GPU memory domain of the submitting process's security context; this is not a KVM guest-to-host escape, IOMMU bypass, or other cross-authority boundary crossing.\nC:H - Incorrect 64-bit user-fence handling on JPEG hardware can cause GPU-initiated writes to unintended addresses in GPU-visible memory, a memory-corruption primitive that can be leveraged for arbitrary kernel/GPU memory disclosure beyond the intended fence buffer.\nI:H - The bug allows the GPU to perform unintended memory writes when processing user-fence completion on a ring that lacks 64-bit user-fence support, providing a writable corruption primitive that could be developed into further code execution or privilege escalation.\nA:H - Submitting unsupported user fences to the JPEG v4.0.3 ring can hang or reset the GPU/firmware and trigger repeated denial of service on affected AMD systems (workstations, laptops, cloud GPU instances) using VCN 4.0.3." } ] } ], "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/jpeg_v4_0_3.c" ], "versions": [ { "version": "e684e654eba9481a9f462a7bbf5c385b7d1c076e", "lessThan": "b884ff67d62ef514eee9d5f605c03101c8b6bc98", "status": "affected", "versionType": "git" }, { "version": "e684e654eba9481a9f462a7bbf5c385b7d1c076e", "lessThan": "d6bd2a5fd611ec9c8a2411f084cff2435c709608", "status": "affected", "versionType": "git" }, { "version": "e684e654eba9481a9f462a7bbf5c385b7d1c076e", "lessThan": "8549b3933038e68dc61cb934b9a54223dd244a78", "status": "affected", "versionType": "git" }, { "version": "e684e654eba9481a9f462a7bbf5c385b7d1c076e", "lessThan": "249fa7549736de1c8e327d7ca6b32fa148a40bd6", "status": "affected", "versionType": "git" }, { "version": "e684e654eba9481a9f462a7bbf5c385b7d1c076e", "lessThan": "83e37c0987ca92f9e87789b46dd311dcf5a4a6c8", "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/jpeg_v4_0_3.c" ], "versions": [ { "version": "6.5", "status": "affected" }, { "version": "0", "lessThan": "6.5", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.141", "lessThanOrEqual": "6.6.*", "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": "6.5", "versionEndExcluding": "6.6.141" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "6.12.91" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "6.18.33" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "7.0.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/b884ff67d62ef514eee9d5f605c03101c8b6bc98" }, { "url": "https://git.kernel.org/stable/c/d6bd2a5fd611ec9c8a2411f084cff2435c709608" }, { "url": "https://git.kernel.org/stable/c/8549b3933038e68dc61cb934b9a54223dd244a78" }, { "url": "https://git.kernel.org/stable/c/249fa7549736de1c8e327d7ca6b32fa148a40bd6" }, { "url": "https://git.kernel.org/stable/c/83e37c0987ca92f9e87789b46dd311dcf5a4a6c8" } ], "title": "drm/amdgpu/jpeg: set no_user_fence for JPEG v4.0.3 ring", "x_generator": { "engine": "bippy-1.2.0" } } } }