{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-74444",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-74444"
  ],
  "published": "2026-08-15T12:28:42Z",
  "summary": "drm/vmwgfx: validate DRAW_PRIMITIVES header size before division",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/vmwgfx: validate DRAW_PRIMITIVES header size before division\n\nvmw_cmd_draw() computes\n\n\tmaxnum = (header->size - sizeof(cmd->body)) / sizeof(*decl);\n\nwhere header->size is u32 and is taken straight from the user-supplied\ncommand stream.  When header->size is less than sizeof(cmd->body) the\nunsigned subtraction wraps to nearly 4 GiB, producing a huge maxnum.\nAny user-controlled cmd->body.numVertexDecls then passes the bound and\nthe loop dereferences decl[i] far past the end of the kernel command\nbounce buffer, producing an out-of-bounds read of kernel memory.\n\nReject undersized headers up front.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.183",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-74444"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/b89ca4bba820f79dde52af15ee139fe6e8bbc314"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/bef30317fcb4c838a37bceb2fc76256eb6b975c1"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/112c6ff29a56f3a22db4d5af869697aa07035ad6"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/2666cddf0dd218aa9bd1f99db688d1b532eac21a"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/fc0c02f510e41650df3479f96e257acf87d8a20a"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/dc0be7662b7b0ce28cb5eea864737793ed7b9e70"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c77cf8edae2bd3a1599115301cc7c98d0c78e731"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/85891d174707d8bddcec7a888fb4e1d17def34f3"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-19T16:47:12Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The bug is reached only through the local DRM_IOCTL_VMW_EXECBUF ioctl (vmw_execbuf_ioctl -> vmw_execbuf_process -> vmw_cmd_check_all -> vmw_cmd_draw); it is not reachable from network, adjacent wireless, or physical buses.\nAC:L - An attacker fully controls the user command stream and can set header->size below sizeof(cmd->body) to underflow maxnum and bypass numVertexDecls bounds; no races or victim-dependent timing are required.\nPR:L - VMW_EXECBUF is registered with DRM_RENDER_ALLOW, so any local process with access to the vmwgfx render node (/dev/dri/renderD*) and a user-created 3D context can submit the malicious DRAW_PRIMITIVES command without real root.\nUI:N - Exploitation requires only the attacker opening the render device and issuing crafted execbuf ioctls; no additional actions by another user or administrator are needed.\nS:U - Impact is confined to the guest kernel address space running vmwgfx (VMware SVGA virtual GPU); successful exploitation yields guest-kernel memory disclosure/corruption and privilege escalation, not a direct hypervisor/host escape.\nC:H - Unsigned underflow makes maxnum enormous, so the vertex-declaration loop dereferences decl[i] far beyond the vmalloc command bounce buffer and reads adjacent kernel heap memory (e.g., decl->array.surfaceId) into validation paths.\nI:H - Beyond disclosure, leaked/adjacent surfaceId values can satisfy vmw_user_resource_lookup_handle and vmw_resource_relocations_apply then writes resource IDs to offsets past the bounce buffer, giving an out-of-bounds kernel write primitive.\nA:H - Setting a large numVertexDecls after the bound bypass can walk far past the vmalloc allocation and fault on unmapped pages, and extensive heap corruption from relocation writes can also trigger kernel oops/panic."
    }
  }
}