{ "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": "2026-10-19T08:53:12.347Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:53:12.347Z" }, "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", "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" }, { "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" } } } }