← Back to CVE Explorer

CVE-2026-74407

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: wifi: ath11k: cancel SSR work items during PCI shutdown A reboot can crash the kernel if it overlaps with WLAN firmware crash recovery (SSR). The crash is a NULL pointer dereference in the MHI teardown path while freeing DMA-backed MHI contexts. Simplified trace: dma_free_attrs mhi_deinit_dev_ctxt [mhi] ath11k_pci_power_down [ath11k_pci] ath11k_pci_shutdown [ath11k_pci] device_shutdown kernel_restart On the host side, SSR is driven by the MHI RDDM callback, which queues reset_work to perform device recovery. reset_work power-cycles the device by calling ath11k_hif_power_down() followed by ath11k_hif_power_up(). The power-down phase deinitializes MHI and frees DMA resources. Shutdown/reboot runs fully asynchronously with this RDDM-driven SSR recovery flow. As a result, the shutdown path (ath11k_pci_shutdown() -> ath11k_pci_power_down()) can race with the SSR recovery sequence. Fix this by canceling SSR-related work items during PCI shutdown, marking the device as unregistering, and serializing the RDDM callback path that checks and queues reset_work. This ensures that no new SSR recovery work can be queued once teardown has started, and that any in-flight recovery work is fully synchronized before device power-down, preventing MHI teardown and DMA resource freeing from running more than once. Note: This issue only affects PCI/MHI-based devices. AHB-based ath11k devices do not queue reset_work in normal SSR flows. Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-04866.5-QCAHSPSWPL_V1_V2_SILICONZ_IOE-1

Severity
HIGH
CVSS score
8.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-15 06:22:42.737000
Last modified
2026-10-30 13:19:57.350000
View original CVE JSON
{
  "id": "CVE-2026-74407",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-15T06:22:42.737",
  "lastModified": "2026-10-30T13:19:57.350",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: ath11k: cancel SSR work items during PCI shutdown\n\nA reboot can crash the kernel if it overlaps with WLAN firmware crash\nrecovery (SSR). The crash is a NULL pointer dereference in the MHI teardown\npath while freeing DMA-backed MHI contexts.\n\nSimplified trace:\n  dma_free_attrs\n  mhi_deinit_dev_ctxt [mhi]\n  ath11k_pci_power_down [ath11k_pci]\n  ath11k_pci_shutdown [ath11k_pci]\n  device_shutdown\n  kernel_restart\n\nOn the host side, SSR is driven by the MHI RDDM callback, which queues\nreset_work to perform device recovery. reset_work power-cycles the device\nby calling ath11k_hif_power_down() followed by ath11k_hif_power_up(). The\npower-down phase deinitializes MHI and frees DMA resources.\n\nShutdown/reboot runs fully asynchronously with this RDDM-driven SSR\nrecovery flow. As a result, the shutdown path\n(ath11k_pci_shutdown() -> ath11k_pci_power_down()) can race with the SSR\nrecovery sequence.\n\nFix this by canceling SSR-related work items during PCI shutdown, marking\nthe device as unregistering, and serializing the RDDM callback path that\nchecks and queues reset_work. This ensures that no new SSR recovery work\ncan be queued once teardown has started, and that any in-flight recovery\nwork is fully synchronized before device power-down, preventing MHI\nteardown and DMA resource freeing from running more than once.\n\nNote: This issue only affects PCI/MHI-based devices. AHB-based ath11k\ndevices do not queue reset_work in normal SSR flows.\n\nTested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-04866.5-QCAHSPSWPL_V1_V2_SILICONZ_IOE-1"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/net/wireless/ath/ath11k/mhi.c",
            "drivers/net/wireless/ath/ath11k/pci.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "13da397f884d9c9a3fb6616206eeb6c6ab097287",
              "lessThan": "7630eb217166435e8a6dd501fa4ad304e2264407",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "13da397f884d9c9a3fb6616206eeb6c6ab097287",
              "lessThan": "f82d42577ee4a191b0ad0f0a3b49fc1935dff845",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "13da397f884d9c9a3fb6616206eeb6c6ab097287",
              "lessThan": "daeb44fb8d700654f37f54d1ee36cd67645d0d34",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "13da397f884d9c9a3fb6616206eeb6c6ab097287",
              "lessThan": "6dd3701facc0cee62d6682e49eed64499f9d0e43",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "13da397f884d9c9a3fb6616206eeb6c6ab097287",
              "lessThan": "53dd29e8aeb2a1b5f079178551836b85fc6b53df",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "13da397f884d9c9a3fb6616206eeb6c6ab097287",
              "lessThan": "8c79aac429b583301f387374ff37c59be671df87",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/net/wireless/ath/ath11k/mhi.c",
            "drivers/net/wireless/ath/ath11k/pci.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.19",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.19",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.114",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.53",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.5",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "attackVector": "ADJACENT_NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T18:55:54.888138Z",
          "id": "CVE-2026-74407",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/53dd29e8aeb2a1b5f079178551836b85fc6b53df",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6dd3701facc0cee62d6682e49eed64499f9d0e43",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7630eb217166435e8a6dd501fa4ad304e2264407",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8c79aac429b583301f387374ff37c59be671df87",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/daeb44fb8d700654f37f54d1ee36cd67645d0d34",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f82d42577ee4a191b0ad0f0a3b49fc1935dff845",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}