CVE-2026-74407 (GCVE-0-2026-74407)
Vulnerability from cvelistv5
Published
2026-08-15 05:59
Modified
2026-08-17 05:46
Severity ?
VLAI Severity ?
EPSS score ?
Summary
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
References
Impacted products
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"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",
"vendor": "Linux",
"versions": [
{
"lessThan": "53dd29e8aeb2a1b5f079178551836b85fc6b53df",
"status": "affected",
"version": "13da397f884d9c9a3fb6616206eeb6c6ab097287",
"versionType": "git"
},
{
"lessThan": "8c79aac429b583301f387374ff37c59be671df87",
"status": "affected",
"version": "13da397f884d9c9a3fb6616206eeb6c6ab097287",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"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",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.19"
},
{
"lessThan": "5.19",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"version": "7.1.5",
"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": "7.1.5",
"versionStartIncluding": "5.19",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2",
"versionStartIncluding": "5.19",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"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() -\u003e 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": {
"baseScore": 8.8,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"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\u2014firmware 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."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-17T05:46:50.498Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"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"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-74407",
"datePublished": "2026-08-15T05:59:16.044Z",
"dateReserved": "2026-08-15T05:44:03.892Z",
"dateUpdated": "2026-08-17T05:46:50.498Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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