{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-68236",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-68236"
  ],
  "published": "2026-08-10T12:08:00Z",
  "summary": "drm/amd/display: set new_stream to NULL after release",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amd/display: set new_stream to NULL after release\n\nIn dm_update_crtc_state(), the skip_modeset path releases new_stream\nvia dc_stream_release() but does not set the pointer to NULL.\n\nIf a later error (e.g., color management failure) triggers the fail\nlabel, the error path calls dc_stream_release() again on the same\ndangling pointer, causing a double release and potential use-after-free.\n\nFix this by setting new_stream to NULL after the initial release.\n\n(cherry picked from commit 99f3af19073b3ddbfd96e789124cce12c4277b28)",
  "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": "6.1.189",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-68236"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/92b7c6e3a1546c6db868b07e93fa6fb950d1d3a0"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/bf9c06c70f496f1ba4474caf95c69696c828340e"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/01ba5b36898d6258f584269537cc49e7b05cf7c6"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ba8bf1dcbb44773e7a0fd13b42925c644e0d5e76"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/5182e442e61397d446c36995b8f5676942d35b82"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/679f23f0a3606afcef1ffabd72222f00a54ad9e3"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/0676fecbb5242aa22c057e78326d6d6041db034c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9fa26b9eed6195bf840f39ac183b9a6237548755"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-10-03T11:04:09Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The bug is reached through the DRM atomic modeset ioctl (DRM_IOCTL_MODE_ATOMIC) on a local /dev/dri/card* node of an AMD GPU; there is no network or remote input path into dm_update_crtc_state().\nAC:L - A single atomic commit that requests a mode change while attaching a wrong-sized DEGAMMA_LUT blob deterministically drives amdgpu_dm_check_crtc_color_mgmt() to -EINVAL and hits the double dc_stream_release(); no race and no uncontrolled precondition, and TEST_ONLY commits let the attacker repeat it freely to groom the heap.\nPR:L - The atomic ioctl is gated only by DRM master on the card node, which any unprivileged local user on a graphical seat or an unused VT can hold; no CAP_SYS_ADMIN or root is needed.\nUI:N - The attacker performs the whole sequence with its own ioctl calls; no action by another user or administrator is required, and TEST_ONLY commits do not even disturb the display.\nS:U - The corrupted dc_stream_state and the resulting freed-memory reuse stay within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The extra kref_put() frees the dc_stream_state while the CRTC state and the DC context still reference it; reading through those dangling pointers after the slab is reallocated leaks adjacent kernel object contents and pointers, and the attacker can spray to control what lands there.\nI:H - The reference-count underflow yields a use-after-free/double-free: subsequent kref_put() writes into reallocated slab memory and dc_stream_free() kfree()s an attacker-influenced update_scratch pointer, giving write and arbitrary-free primitives usable for privilege escalation.\nA:H - Even without exploitation the premature free causes dereference of freed stream/sink/link structures during atomic state unwind, producing a kernel oops or panic and killing the display pipeline; it can be triggered repeatedly."
    }
  }
}