From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-74412][MODERATE 7.0] wifi: rtw88: fix wrong pci_get_drvdata type in AER handlers [ Upstream Date: Sun, 16 Aug 2026 00:51:02 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-74412 X-AL-KERNEL-Priority: MODERATE 7.0 X-AL-KERNEL-Severity: MODERATE 7.0 X-AL-KERNEL-Base-Severity: MODERATE X-AL-KERNEL-KPANIC: NO X-AL-KERNEL-ActionableScore: 5 X-AL-KERNEL-ActionableScore-Lower: 3 X-AL-KERNEL-Commit: 1ef3d1338d94ec41f58fbfb6ba7742a27ea61d89 List-Id: CVE: CVE-2026-74412 Priority: MODERATE 7.0 AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: wifi: rtw88: fix wrong pci_get_drvdata type in AER handlers [ Upstream Commit: 1ef3d1338d94ec41f58fbfb6ba7742a27ea61d89 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1ef3d1338d94ec41f58fbfb6ba7742a27ea61d89 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-74412 Analysis date: Sun, 16 Aug 2026 00:51:02 -0400 ActionableScore: 5 ActionableScore lower bound: 3 Actionable bucket: Strong Important candidate / Actionable Moderate at minimum Manual review required: YES Summary: The rtw88 PCI AER handlers used an ieee80211_hw pointer as a net_device pointer, causing wrong-offset kernel reads and writes during PCI error recovery and creating a device-error-path type confusion that can crash or corrupt kernel driver state. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-74412 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-74412 The original announcement does not normally provide a security severity estimate, CVSS assessment, or enough information to determine whether the reported kernel bug represents a practically relevant security issue. This report was generated by AL-KERNEL, an AI-assisted Linux kernel vulnerability analysis system developed by Alexander Larkin. It combines an autonomous classifier with LLM-assisted technical analysis and a separate ActionableScore mechanism. The purpose of this report is to prioritize Linux kernel CVEs before manual review, identify cases that require prompt investigation, and support automatic closure of issues that are unlikely to have meaningful security impact. Published priority for this report: MODERATE 7.0 Manual review required: YES A detailed explanation of the methodology and priority rules is included at the end of this message. ====================================================================== AL-KERNEL CLASSIFICATION RESULT ====================================================================== CVE-2026-74412 MODERATE CHECK WITH IMPACT FROM ORIG NN IMPORTANT Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H';CWE-843;*CWE-787;CWE-119;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:H';BEST CVSS score: '7';DESCR 'The rtw88 PCI AER handlers retrieved pci driver data as a net_device pointer even though probe stored an ieee80211_hw pointer. As a result, netif_device_detach and netif_device_attach could operate on the wrong object type and access fields at net_device offsets inside an ieee80211_hw object. This is a kernel type confusion bug with wrong offset reads and writes, so the impact is at least a local denial of service via crash or corrupted driver state and in the worst case may allow broader memory corruption. For the CVSS the PR:L in the paranoid score reflects environments where a local low privileged process can indirectly trigger PCI error recovery or device recovery through exposed management paths, while the base score keeps PR:H for typical systems where AER injection and driver reset control are administrative. The issue is not directly network reachable from normal WiFi traffic and exploitation requires reaching the PCIe error recovery path for an affected rtw88 device.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Strong Important candidate / Actionable Moderate at minimum (with actual score 4) YES REMOTE DANGER SIMPLEFIX ERRORPATH NETWORK LINUS DECREASED_TO_MODERATE70_BASED_ON_ACTIONABLESCORELOWERTHAN6 DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN5 YES NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=5 ActionableScoreLower=3 ## 1. ActionableScore * Conservative score: 3 * Paranoid score: 5 * Final recommended bucket: **Strong Important candidate / Actionable Moderate at minimum**:: ## 2. Signal breakdown Conservative signals: * Memory corruption, weak/indirect corruption candidate: +1 The patch fixes a real type mismatch where an `ieee80211_hw *` is interpreted as `struct net_device *`, causing helper functions to read and write fields at wrong offsets. * Reliable kernel crash / strong DoS: +1 If the PCI AER recovery path is reached, wrong-object access can plausibly corrupt driver state or crash the kernel. * Privileged kernel/device-management memory corruption path: +1 The bug is in PCIe AER recovery for a wireless PCI driver, a trusted device-management path. * Requires admin/root/CAP_* in typical deployments: -2 Reliable triggering usually requires PCIe AER injection, reset control, fault injection, or a real device error, which is normally administrative or hardware-mediated. * Rare/difficult-to-reach path: -1 PCIe AER error recovery is not a normal packet receive/transmit path and is not usually attacker-triggerable on demand. Paranoid additional interpretation: * Firmware-mediated external influence: +1 The affected path can be entered due to PCIe/device/firmware error conditions, even though this is not normal remote network reachability. * Weak LPE concern: +1 Wrong-offset writes through `netif_device_detach/attach()` create a type-confusion corruption sink. There is no demonstrated reclaim or arbitrary write primitive, so this is weak rather than strong LPE plausibility. * Reduced privilege interpretation: +1 effective uplift In some environments, device recovery or reset-like behavior may be exposed to service accounts, container-adjacent management tooling, or reduced-capability root, so treating this strictly as PR:H may understate practical risk. Call-site confidence: high. The changed call sites and the incorrect helper calls are visible in the patch. ## 3. Reachability analysis The bug is triggered when the rtw88 PCI AER handlers run. In typical deployments this requires PCIe AER recovery, device error handling, fault injection, or reset/error conditions, not ordinary WiFi traffic. A remote WiFi peer is not shown to be able to trigger this directly. Local unprivileged reachability is not demonstrated. Conservative scoring treats the trigger as administrative or hardware-mediated. The paranoid score allows for environments where device recovery paths may be indirectly influenced by less-privileged local actors or by faulty/malicious device behavior. Namespaces and containers do not normally provide access to PCIe AER injection or host device reset. If a container or service is delegated device-management privileges, the PR assessment should be revisited. ## 4. Severity interpretation This is more than an ordinary correctness bug because it is a real kernel type confusion with wrong-offset reads and writes. However, the reachable path is narrow and device-error dependent, and there is no demonstrated attacker-controlled overwrite, object reclaim, callback control, or arbitrary write primitive. Realistically, this behaves like a local or device-mediated DoS/corruption issue. Paranoid triage should keep it as Actionable Moderate because the bug class is memory corruption in a trusted kernel driver error path and could hide a stronger primitive after manual review. It is not a clear Important issue without evidence that an unprivileged user can reliably trigger AER recovery or control the corrupted fields. ## 5. One-sentence report phrase The rtw88 PCI AER handlers used an ieee80211_hw pointer as a net_device pointer, causing wrong-offset kernel reads and writes during PCI error recovery and creating a device-error-path type confusion that can crash or corrupt kernel driver state. ## 6. Manual review recommendation MANUAL CHECK REQUIRED Reason: the patch fixes a concrete type confusion with writes through the wrong structure type. The main uncertainty is reachability, not whether the bug is memory-corruption relevant. Manual review should focus on whether affected hardware, firmware behavior, reset paths, or delegated device-management interfaces allow a practical non-admin trigger. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: rtw88: fix wrong pci_get_drvdata type in AER handlers [ Upstream Commit: 1ef3d1338d94ec41f58fbfb6ba7742a27ea61d89 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1ef3d1338d94ec41f58fbfb6ba7742a27ea61d89 Changed files: drivers/net/wireless/realtek/rtw88/pci.c Diff excerpt: Not included in this email. See the upstream URL for the full patch. Full patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1ef3d1338d94ec41f58fbfb6ba7742a27ea61d89 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-74412 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-74412 The original CVE announcement normally does not include a security-level estimate. In particular, it may not contain a CVSS assessment, an impact level, or enough information to determine whether the reported bug is a practically relevant security issue. One purpose of this parallel CVE list is to provide that missing technical and prioritization information. The original goal of the AL-KERNEL project was to prioritize Linux kernel CVE analysis automatically before manual review. The system can also help identify non-security issues that may be suitable for automatic closure. This report was generated by AL-KERNEL, an AI-assisted Linux kernel vulnerability analysis system developed by Alexander Larkin. The first analysis stage combines an autonomous classifier with additional LLM-based analysis. The autonomous classifier runs locally on a CPU and is based on a backpropagation neural network. Together, these mechanisms produce a technical vulnerability description, identify likely weakness types, estimate CVSS severity, and provide input for ActionableScore. Two CVSS estimates are retained because incomplete kernel vulnerability information often permits more than one defensible interpretation: Conservative CVSS vector: AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:H The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H The Best / paranoid CVSS score: 7 The conservative vector represents a lower-impact interpretation. The Best/paranoid vector intentionally represents a plausible upper-bound interpretation and should not automatically be treated as demonstrated real-world impact. CVSS may also need to be adjusted for a particular Linux deployment, because actual reachability, privileges, enabled kernel configuration, hardware, namespaces, exposed device nodes, and other environmental conditions can differ significantly between systems. A separate ActionableScore mechanism evaluates practical remediation urgency. Its analysis may include reachability, attack prerequisites, subsystem exposure, memory-corruption characteristics, denial-of-service reliability, and possible confidentiality, integrity, or privilege-escalation impact. Conservative ActionableScore: 3 Paranoid ActionableScore: 5 The final base severity is taken directly from the second tab-separated field of the AL-KERNEL classification result. ActionableScore does not replace or independently override that final AL-KERNEL decision, and if ActionableScore adjusted impact level of ALKERNEL, then you would see self-readable flags above like INCREASED_TO_HIGH_BASED_ON_ACTIONABLESCOREHIGHEREQTHAN7. For an AL-KERNEL result of MODERATE, this report uses the following additional presentation split: ActionableScore below 5 -> MODERATE REGULAR ActionableScore 5 or more -> MODERATE 7.0 The distinction between MODERATE REGULAR and MODERATE 7.0 makes it possible to identify Moderate issues that should receive manual analysis and fixes before lower-priority MODERATE REGULAR issues. In many cases, MODERATE REGULAR fixes may wait for a later rebase or routine update. There is one override in which MODERATE REGULAR becomes MODERATE 7.0 even when the ActionableScore is below 5. When the AL-KERNEL result contains the KPANIC flag, a MODERATE result is always presented as MODERATE 7.0. The KPANIC flag selected with few regexps without usage of AI at all, so it helps to detect cases when Kernel Crash happens and similar (to filter False-Negative results from the LLM usage). KPANIC indicates that a reliable kernel crash, kernel panic, or similarly serious kernel availability impact was identified by the classification workflow. AL-KERNEL base severity for this report: MODERATE KPANIC detected for this report: NO Published priority for this report (same as in Subject): MODERATE 7.0 These results are intended to support engineering triage. They are machine-generated estimates, and cases marked for manual review should be validated by a human security engineer before final disposition. For more info read docs linked from here: https://kernelcve.org/ (and you can submit you own patch there to generate such a report for non-existant CVE-id yet). Note that in many cases this AI tool selects higher severity, than real is (means you can expect Importants instead of Moderate 7.0 or Moderates 7.0 instead of regular Moderates). If you see such cases, please use reply email interface to add additional manual analyses info to this particular CVE. And please, please, let me know when you see Lows instead of Importants or Important instead of Low (because particular for such cases I need to tune this AI tool to make it better for this one and next similar). My contact email for such notifications is alexanjelausa@gmail.com (and both send reply to CVE record itself too and see "reply" button below for howto reply).