Vulnerability-Lookup

FKIE_CVE-2026-68445

Vulnerability from fkie_nvd - Published: 2026-08-12 00:17 - Updated: 2026-08-17 06:17

Severity

7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: drm/vc4: Prevent shader BO mappings from becoming writable vc4_gem_object_mmap() rejects a writable mapping of a validated shader BO, but leaves VM_MAYWRITE set. Userspace can map the BO read-only and then turn it writable with mprotect(). Validated shader BOs must stay read-only: the validator checks the instructions once and the GPU trusts them afterwards. A writable mapping lets userspace rewrite the code after validation, bypassing the validator. Clear VM_MAYWRITE on the read-only path so the mapping cannot be upgraded, as i915 already does for its read-only objects.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/019e6ad247f7fd038d2e009789f6d9bfcccb1ae7
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/0c9e6367639548307d3f578f6943ce72c9d39087
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/6deaa317201851c644c431b57682e54d06b35838
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/9f0ee411fc2d76333d6087c5862ffa907cf7a175
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/fe168ef1d232d734d9998fd74822e2e20930dfff

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/vc4/vc4_bo.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "9f0ee411fc2d76333d6087c5862ffa907cf7a175",
              "status": "affected",
              "version": "463873d5701427f2964a0b4b72c45f1f14b6df87",
              "versionType": "git"
            },
            {
              "lessThan": "019e6ad247f7fd038d2e009789f6d9bfcccb1ae7",
              "status": "affected",
              "version": "463873d5701427f2964a0b4b72c45f1f14b6df87",
              "versionType": "git"
            },
            {
              "lessThan": "6deaa317201851c644c431b57682e54d06b35838",
              "status": "affected",
              "version": "463873d5701427f2964a0b4b72c45f1f14b6df87",
              "versionType": "git"
            },
            {
              "lessThan": "fe168ef1d232d734d9998fd74822e2e20930dfff",
              "status": "affected",
              "version": "463873d5701427f2964a0b4b72c45f1f14b6df87",
              "versionType": "git"
            },
            {
              "lessThan": "0c9e6367639548307d3f578f6943ce72c9d39087",
              "status": "affected",
              "version": "463873d5701427f2964a0b4b72c45f1f14b6df87",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/vc4/vc4_bo.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.5"
            },
            {
              "lessThan": "4.5",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.148",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.101",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "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."
    }
  ],
  "id": "CVE-2026-68445",
  "lastModified": "2026-08-17T06:17:53.560",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-12T00:17:44.860",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/019e6ad247f7fd038d2e009789f6d9bfcccb1ae7"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0c9e6367639548307d3f578f6943ce72c9d39087"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/6deaa317201851c644c431b57682e54d06b35838"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/9f0ee411fc2d76333d6087c5862ffa907cf7a175"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fe168ef1d232d734d9998fd74822e2e20930dfff"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

CVE-2026-68445 (GCVE-0-2026-68445)

Vulnerability from cvelistv5 – Published: 2026-08-12 00:07 – Updated: 2026-08-17 05:05

Title

drm/vc4: Prevent shader BO mappings from becoming writable

Summary

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux mitre root

References

5 references

URL	Tags
https://git.kernel.org/stable/c/9f0ee411fc2d76333…
https://git.kernel.org/stable/c/019e6ad247f7fd038…
https://git.kernel.org/stable/c/6deaa317201851c64…
https://git.kernel.org/stable/c/fe168ef1d232d734d…
https://git.kernel.org/stable/c/0c9e6367639548307…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 463873d5701427f2964a0b4b72c45f1f14b6df87 , < 9f0ee411fc2d76333d6087c5862ffa907cf7a175 (git) Affected: 463873d5701427f2964a0b4b72c45f1f14b6df87 , < 019e6ad247f7fd038d2e009789f6d9bfcccb1ae7 (git) Affected: 463873d5701427f2964a0b4b72c45f1f14b6df87 , < 6deaa317201851c644c431b57682e54d06b35838 (git) Affected: 463873d5701427f2964a0b4b72c45f1f14b6df87 , < fe168ef1d232d734d9998fd74822e2e20930dfff (git) Affected: 463873d5701427f2964a0b4b72c45f1f14b6df87 , < 0c9e6367639548307d3f578f6943ce72c9d39087 (git)
Linux	Linux	Affected: 4.5 Unaffected: 0 , < 4.5 (semver) Unaffected: 6.6.148 , ≤ 6.6.* (semver) Unaffected: 6.12.101 , ≤ 6.12.* (semver) Unaffected: 6.18.42 , ≤ 6.18.* (semver) Unaffected: 7.1.6 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/vc4/vc4_bo.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "9f0ee411fc2d76333d6087c5862ffa907cf7a175",
              "status": "affected",
              "version": "463873d5701427f2964a0b4b72c45f1f14b6df87",
              "versionType": "git"
            },
            {
              "lessThan": "019e6ad247f7fd038d2e009789f6d9bfcccb1ae7",
              "status": "affected",
              "version": "463873d5701427f2964a0b4b72c45f1f14b6df87",
              "versionType": "git"
            },
            {
              "lessThan": "6deaa317201851c644c431b57682e54d06b35838",
              "status": "affected",
              "version": "463873d5701427f2964a0b4b72c45f1f14b6df87",
              "versionType": "git"
            },
            {
              "lessThan": "fe168ef1d232d734d9998fd74822e2e20930dfff",
              "status": "affected",
              "version": "463873d5701427f2964a0b4b72c45f1f14b6df87",
              "versionType": "git"
            },
            {
              "lessThan": "0c9e6367639548307d3f578f6943ce72c9d39087",
              "status": "affected",
              "version": "463873d5701427f2964a0b4b72c45f1f14b6df87",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/vc4/vc4_bo.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.5"
            },
            {
              "lessThan": "4.5",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.148",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.101",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.148",
                  "versionStartIncluding": "4.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.101",
                  "versionStartIncluding": "4.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.42",
                  "versionStartIncluding": "4.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.6",
                  "versionStartIncluding": "4.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "4.5",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "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": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "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\u0027s 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 \u2014 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."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:05:42.989Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "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"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-68445",
    "datePublished": "2026-08-12T00:07:36.230Z",
    "dateReserved": "2026-07-30T09:28:09.394Z",
    "dateUpdated": "2026-08-17T05:05:42.989Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

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FKIE_CVE-2026-68445

CVE-2026-68445 (GCVE-0-2026-68445)

Tags

Sightings

Nomenclature