{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74407","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-08-15T05:44:03.892Z","datePublished":"2026-08-15T05:59:16.044Z","dateUpdated":"2026-08-17T05:46:50.498Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-17T05:46:50.498Z"},"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"}],"metrics":[{"cvssV3_1":{"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"},"scenarios":[{"lang":"en","value":"AV:A - WiFi ath11k PCI/MHI devices (QCA6390/WCN6855 laptops, workstations, gateways) enter SSR when WLAN firmware faults; MHI RDDM interrupts queue reset_work recovery that races kernel_restart PCI shutdown (ath11k_pci_shutdown) on the same driver.\nAC:L - An adjacent attacker controls SSR timing by repeatedly inducing firmware crashes via crafted/malicious 802.11 traffic, keeping reset_work active until shutdown overlaps; this is an attacker-driven race, not luck-dependent memory layout or rare kernel config.\nPR:N - No Linux account or kernel capability is needed to trigger the SSR leg—firmware crash/RDDM recovery is driven by over-the-air WLAN events; concurrent device_shutdown during automated maintenance or fleet reboots can overlap without attacker CAP_SYS_BOOT.\nUI:N - Only an active ath11k WLAN interface is required (default on WiFi-equipped systems); no victim clicks, network joins, or manual reboot actions are needed because unattended updates and scheduled maintenance reboots can overlap SSR automatically.\nS:U - Impact is kernel panic/oops from unsynchronized MHI DMA teardown within the host kernel security boundary; this does not cross VM, container, or IOMMU trust domains.\nC:H - Concurrent mhi_unprepare_after_power_down/mhi_deinit_dev_ctxt from reset_work and ath11k_pci_shutdown can double-free coherent DMA rings/contexts or dereference freed MHI state, enabling arbitrary kernel memory reads and information disclosure.\nI:H - Racing power-down paths free the same MHI DMA-backed ring/context memory twice, corrupting kernel DMA allocator metadata and enabling controlled reallocation for arbitrary kernel writes, control-flow hijack, and privilege escalation.\nA:H - NULL pointer dereference and/or double dma_free in mhi_deinit_dev_ctxt during PCI shutdown overlapping SSR reliably causes kernel oops/panic, denying availability and potentially aborting reboot on affected Qualcomm ath11k PCI systems."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/wireless/ath/ath11k/mhi.c","drivers/net/wireless/ath/ath11k/pci.c"],"versions":[{"version":"13da397f884d9c9a3fb6616206eeb6c6ab097287","lessThan":"53dd29e8aeb2a1b5f079178551836b85fc6b53df","status":"affected","versionType":"git"},{"version":"13da397f884d9c9a3fb6616206eeb6c6ab097287","lessThan":"8c79aac429b583301f387374ff37c59be671df87","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/net/wireless/ath/ath11k/mhi.c","drivers/net/wireless/ath/ath11k/pci.c"],"versions":[{"version":"5.19","status":"affected"},{"version":"0","lessThan":"5.19","status":"unaffected","versionType":"semver"},{"version":"7.1.5","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":"5.19","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.19","versionEndExcluding":"7.2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/53dd29e8aeb2a1b5f079178551836b85fc6b53df"},{"url":"https://git.kernel.org/stable/c/8c79aac429b583301f387374ff37c59be671df87"}],"title":"wifi: ath11k: cancel SSR work items during PCI shutdown","x_generator":{"engine":"bippy-1.2.0"}}}}