{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-68445", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.394Z", "datePublished": "2026-08-12T00:07:36.230Z", "dateUpdated": "2026-08-17T05:05:42.989Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:05:42.989Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/vc4: Prevent shader BO mappings from becoming writable\n\nvc4_gem_object_mmap() rejects a writable mapping of a validated shader\nBO, but leaves VM_MAYWRITE set. Userspace can map the BO read-only and\nthen turn it writable with mprotect().\n\nValidated shader BOs must stay read-only: the validator checks the\ninstructions once and the GPU trusts them afterwards. A writable\nmapping lets userspace rewrite the code after validation, bypassing the\nvalidator.\n\nClear VM_MAYWRITE on the read-only path so the mapping cannot be\nupgraded, as i915 already does for its read-only objects." } ], "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 vc4 DRM render node (/dev/dri/renderD*) to issue VC4_CREATE_SHADER_BO, VC4_MMAP_BO, mmap/mprotect and VC4_SUBMIT_CL; there is no remote or network-facing path to this code.\nAC:L - The attacker fully controls every step: create a shader that passes validation, map it PROT_READ, upgrade it with mprotect(PROT_WRITE), rewrite the instructions and submit. There is no race, no memory-layout dependency, and it works on the default configuration of any VC4 (Raspberry Pi) system.\nPR:L - VC4_CREATE_SHADER_BO, VC4_MMAP_BO and VC4_SUBMIT_CL are all DRM_RENDER_ALLOW ioctls, so an ordinary unprivileged user with render-node access (the default for logged-in/graphical users on Raspberry Pi and embedded VC4 devices) can perform the whole sequence. No capability check is involved.\nUI:N - The attacking process performs the entire sequence itself; no action by another user or administrator is needed.\nS:U - The vulnerable driver and the compromised resource (kernel/system memory) are both under the kernel's security authority; this is a standard local kernel privilege escalation rather than a VM or hypervisor boundary escape.\nC:H - Post-validation rewriting of shader code lets the GPU, which has no IOMMU on VC4, read arbitrary system memory via texture, uniform and direct-addressed TMU lookups — exactly the disclosure the validator exists to prevent, giving arbitrary kernel memory read.\nI:H - Unvalidated QPU code can use the VPM write address register in general-purpose DMA mode to write to arbitrary physical addresses, an arbitrary kernel-memory write primitive that yields full privilege escalation and code execution.\nA:H - The same arbitrary DMA writes and unbounded shader execution readily corrupt kernel structures or hang the GPU, causing kernel panics or a full system hang triggerable at will by an unprivileged user." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/gpu/drm/vc4/vc4_bo.c" ], "versions": [ { "version": "463873d5701427f2964a0b4b72c45f1f14b6df87", "lessThan": "9f0ee411fc2d76333d6087c5862ffa907cf7a175", "status": "affected", "versionType": "git" }, { "version": "463873d5701427f2964a0b4b72c45f1f14b6df87", "lessThan": "019e6ad247f7fd038d2e009789f6d9bfcccb1ae7", "status": "affected", "versionType": "git" }, { "version": "463873d5701427f2964a0b4b72c45f1f14b6df87", "lessThan": "6deaa317201851c644c431b57682e54d06b35838", "status": "affected", "versionType": "git" }, { "version": "463873d5701427f2964a0b4b72c45f1f14b6df87", "lessThan": "fe168ef1d232d734d9998fd74822e2e20930dfff", "status": "affected", "versionType": "git" }, { "version": "463873d5701427f2964a0b4b72c45f1f14b6df87", "lessThan": "0c9e6367639548307d3f578f6943ce72c9d39087", "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/vc4/vc4_bo.c" ], "versions": [ { "version": "4.5", "status": "affected" }, { "version": "0", "lessThan": "4.5", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.148", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.101", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.6", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "4.5", "versionEndExcluding": "6.6.148" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.5", "versionEndExcluding": "6.12.101" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.5", "versionEndExcluding": "6.18.42" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.5", "versionEndExcluding": "7.1.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.5", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/9f0ee411fc2d76333d6087c5862ffa907cf7a175" }, { "url": "https://git.kernel.org/stable/c/019e6ad247f7fd038d2e009789f6d9bfcccb1ae7" }, { "url": "https://git.kernel.org/stable/c/6deaa317201851c644c431b57682e54d06b35838" }, { "url": "https://git.kernel.org/stable/c/fe168ef1d232d734d9998fd74822e2e20930dfff" }, { "url": "https://git.kernel.org/stable/c/0c9e6367639548307d3f578f6943ce72c9d39087" } ], "title": "drm/vc4: Prevent shader BO mappings from becoming writable", "x_generator": { "engine": "bippy-1.2.0" } } } }