From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-68307][MODERATE REGULAR] wifi: mt76: mt7925: fix crash in reset link replay [ Upstream Date: Mon, 10 Aug 2026 14:42:44 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-68307 X-AL-KERNEL-Priority: MODERATE REGULAR X-AL-KERNEL-Severity: MODERATE REGULAR X-AL-KERNEL-Base-Severity: MODERATE X-AL-KERNEL-KPANIC: NO X-AL-KERNEL-ActionableScore: 3 X-AL-KERNEL-ActionableScore-Lower: 1 X-AL-KERNEL-Commit: d9326796a378f80be5f9fd60983c62fdccdf2f0b List-Id: CVE: CVE-2026-68307 Priority: MODERATE REGULAR AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: wifi: mt76: mt7925: fix crash in reset link replay [ Upstream Commit: d9326796a378f80be5f9fd60983c62fdccdf2f0b Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d9326796a378f80be5f9fd60983c62fdccdf2f0b Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68307 Analysis date: Mon, 10 Aug 2026 14:42:44 -0400 ActionableScore: 3 ActionableScore lower bound: 1 Actionable bucket: Borderline, manual review recommended Manual review required: YES Summary: A NULL pointer dereference in the mt76 mt7925 reset recovery path can crash the kernel when stale `valid_links` state causes firmware link replay to use a missing mac80211 `bss_conf`, with practical exposure depending on affected hardware, MLO behavior, and whether wireless-adjacent conditions can trigger reset recovery. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-68307 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68307 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 REGULAR 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-2026-68307 MODERATE CHECK WITH IMPACT FROM ORIG NN IMPORTANT Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H';**CWE-476;CWE-703;CWE-362;Other CVSS 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '5.3';DESCR 'A NULL pointer dereference in the mt76 mt7925 reset recovery path can occur because mt7925_vif_connect_iter can replay firmware state for a link that remains set in mvif valid_links after the mac80211 bss_conf has already gone away. This passes a NULL bss_conf into mt76_connac_mcu_uni_add_dev and can crash the kernel from the reset workqueue. For the CVSS the PR:N is used in the paranoid adjacent network scenario because a nearby attacker or malicious AP may be able to influence MLO link changes or recovery conditions without local access to the victim. The issue is not Internet reachable and requires WiFi adjacency plus affected mt7925 hardware and relevant MLO or reset recovery conditions. Impact is denial of service only via kernel crash. No confidentiality or integrity impact is assigned because the visible primitive is a NULL pointer dereference rather than UAF, OOB write, or information disclosure.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline, manual review recommended (with actual score 2) YES REMOTE DANGER NETWORK KERNEL_PANIC_PLUS_UAF LOWERED_FROM_HIGH_BASED_ON_GUESSCVSS DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN5 YES NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=3 ActionableScoreLower=1 ## 1. ActionableScore * Conservative score: 1 * Paranoid score: 3 * Final recommended bucket: **Borderline, manual review recommended** ## 2. Signal breakdown Conservative signals: * Reliable kernel crash / strong DoS: +1 The commit shows a concrete NULL `bss_conf` passed into `mt76_connac_mcu_uni_add_dev()`, with a crash trace from `mt7925_mac_reset_work()`. Paranoid additional signals: * Firmware-mediated external influence: +1 The vulnerable state occurs during reset recovery after MLO link changes or MCU timeout recovery. A nearby AP, hostile wireless environment, or firmware recovery condition may plausibly influence this path, but this is not ordinary Internet remote reachability. * Availability impact realistic: +1 The failure mode is a kernel crash from a workqueue, not just a warning or benign failed operation. Negative or limiting signals: * Hard or special trigger conditions: -1 in conservative reasoning The issue depends on mt7925 hardware, reset recovery, MLO link state, and a transient mismatch between `mvif->valid_links` and mac80211 `bss_conf`. * Rare / device-specific exposure: -1 in conservative reasoning This affects a specific MediaTek WiFi driver path, not a broad networking core path. No added signals: * No generic memory corruption bonus. The visible primitive is NULL pointer dereference, not UAF, OOB write, double free, or type confusion. * No privilege escalation bonus. The patch does not show reclaim, overwrite, callback control, refcount abuse, or attacker-controlled object replacement. * No confidentiality or integrity impact. There is no disclosure or write primitive. ## 3. Reachability analysis The conservative trigger is local or system-driven: a user or WiFi management stack causes link changes, reset recovery, or firmware timeout recovery on an affected mt7925 device. In normal deployments, direct control over driver reset and interface management may require elevated privileges or a privileged network manager. The paranoid trigger is adjacent-network influenced: a nearby AP or hostile wireless environment may be able to influence MLO link changes or recovery conditions, but this is not a normal AV:N network service and not Internet reachable. The path is only relevant on systems with affected mt7925 hardware and relevant MLO/reset recovery behavior. Namespaces and containers do not materially improve reachability unless the container or namespace has delegated control over the WiFi device. This is not a common container-exposed interface. Call-site confidence: high. The provided diff shows the NULL check immediately before the call that crashed. ## 4. Severity interpretation This behaves like a device-specific DoS issue, not an Important-class memory corruption vulnerability. The theoretical risk is limited because the bad pointer is NULL and the patch does not indicate UAF, stale object reuse, writable corruption, or object confusion. The paranoid score is raised only because wireless adjacency and firmware/reset recovery can make practical triggerability non-obvious and worth manual review. It should not be auto-promoted to Important based on the patch alone. ## 5. One-sentence report phrase A NULL pointer dereference in the mt76 mt7925 reset recovery path can crash the kernel when stale `valid_links` state causes firmware link replay to use a missing mac80211 `bss_conf`, with practical exposure depending on affected hardware, MLO behavior, and whether wireless-adjacent conditions can trigger reset recovery. ## 6. Manual review recommendation MANUAL CHECK RECOMMENDED Reason: the bug is DoS-only by visible primitive, but wireless-adjacent triggerability depends on mt7925 hardware, MLO link behavior, firmware timeout recovery, and environmental influence from APs or nearby attackers. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: mt76: mt7925: fix crash in reset link replay [ Upstream Commit: d9326796a378f80be5f9fd60983c62fdccdf2f0b Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d9326796a378f80be5f9fd60983c62fdccdf2f0b Changed files: drivers/net/wireless/mediatek/mt76/mt7925/mac.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=d9326796a378f80be5f9fd60983c62fdccdf2f0b ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-68307 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68307 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:L/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS vector: AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 5.3 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: 1 Paranoid ActionableScore: 3 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 REGULAR 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).