From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-98334][LOW] wifi: mac80211: reset state when starting AP fails [ Upstream Date: Sat, 10 Oct 2026 05:45:13 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-98334 X-AL-KERNEL-Priority: LOW X-AL-KERNEL-Severity: LOW X-AL-KERNEL-Base-Severity: LOW X-AL-KERNEL-KPANIC: NO X-AL-KERNEL-ActionableScore: 1 X-AL-KERNEL-ActionableScore-Lower: unknown X-AL-KERNEL-Commit: d83da43e9b3b3b1bad99ac5a1065f1c63ad5fc32 List-Id: CVE: CVE-2026-98334 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: wifi: mac80211: reset state when starting AP fails [ Upstream Commit: d83da43e9b3b3b1bad99ac5a1065f1c63ad5fc32 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d83da43e9b3b3b1bad99ac5a1065f1c63ad5fc32 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98334 Analysis date: Sat, 10 Oct 2026 05:45:13 -0400 ActionableScore: 1 ActionableScore lower bound: unknown Actionable bucket: Ordinary Moderate Manual review required: NO Summary: No one-sentence report phrase was found. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98334 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98334 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: LOW Manual review required: NO A detailed explanation of the methodology and priority rules is included at the end of this message. ====================================================================== AL-KERNEL CLASSIFICATION RESULT ====================================================================== CVE-2026-98334 LOW https://www.kernelcve.org/list/?q=CVE-2026-98334 CHECK WITH IMPACT FROM ORIG NN LOW | AEGIS IMPACT MODERATE_KPANIC AEGIS_AS=0 LEGACY=LOW RESULT=DIFF TEMP_DISTANCE_MERGE_SKIP=AEGIS_NO_POSITIVE_SEVERITY_EVIDENCE (independent Legacy and Aegis differ; FINAL: LOW, Aegis: MODERATE_KPANIC) Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H';CWE-369;CWE-665;CWE-703;Other CVSS 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '5.5';DESCR 'A failed ieee80211_start_ap operation can leave enable_beacon and beacon_int in an inconsistent state even though AP startup did not complete. A later scan or off channel transition can treat beaconing as active and reach a divide by zero in mac80211_hwsim, producing a kernel Oops and potentially a kernel panic depending on system configuration. For the CVSS the PR:L value is used because a local user or service with delegated CAP_NET_ADMIN can configure the wireless interface and initiate the required AP and scan operations without having unrestricted host administrator privileges. The issue is not directly network reachable because received wireless traffic alone does not perform the required control plane configuration sequence. Impact is denial of service. There is no supported UAF, out of bounds access, or other memory corruption primitive that would justify confidentiality or integrity impact.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1) MAYBE REMOTE KASAN SYZBOT DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=1 PrimitiveClass=CLASS_C RealUAF=NO HostAdminRequired=UNKNOWN NamespaceScopedPrivilege=UNKNOWN ImportantCandidate=NO ManualReview=NO AutoDowngradeAllowed=YES RequiresHostUID0=UNKNOWN AuthorizationDecisionBypass=NO ProtectedResourceImpact=NONE B4PendingReview=NO B4PendingConfirmed=NO 1. ActionableScore * Raw conservative score: 1 * Conservative score: 1 * Raw paranoid score: 1 * Paranoid score: 1 * No floor or cap was applied. * Final recommended bucket: **Ordinary Moderate**:: 2. Signal breakdown Positive signals: * +1 Reliable kernel fault and denial of service. A failed AP startup followed by scanning can reach a divide error in `mac80211_hwsim_link_info_changed()` and produce a kernel Oops. A full panic depends on configuration such as `panic_on_oops`. * No additional availability point was awarded because the warning, Oops, and possible panic describe the same stale-state failure. Negative signals: * No negative privilege penalty was applied because host-admin-equivalent privilege is not positively established. * No race penalty was applied. This is an ordered state-management failure rather than a timing race. * No rare-hardware penalty was applied. The demonstrated path uses mac80211 hwsim, but the evidence does not establish a physical-only requirement. Material non-awarded signals: * No UAF, OOB access, heap overwrite, repeated release, refcount corruption, or controlled reclaim is established. * NEW52 B5-R does not apply because there is no confirmed retry-accumulated heap OOB write or later consumption of corrupted heap state. * NEW53 B3-PENDING does not apply because no shared-backing or file-backed write is present. * No authorization decision changes from DENY to ALLOW. NEW54 B4-PENDING therefore does not apply. * Remote reachability is not established. Wireless packets alone do not invoke the required AP configuration and scan sequence. * Local unprivileged trigger was not awarded because complete below-capability reachability is not demonstrated. * Confidentiality, integrity, privilege escalation, and arbitrary write effects are not supported. 3. Reachability analysis The trigger requires control-plane operations that start an AP, reach a later failure after beacon state has been set, and then initiate scanning or an off-channel transition. These operations normally involve nl80211 and CAP_NET_ADMIN over the relevant wireless object. A delegated network-management service may be able to exercise the runtime sequence without full host-administrator powers. However, the supplied evidence does not resolve which user namespace governs every required check, whether the actor can obtain and control a suitable wiphy, or whether hwsim creation and provisioning require prior host administration. Consequently, both host-admin and complete namespace-scoped reachability remain unknown. The demonstrated reproducer uses mac80211 hwsim. Prior module loading or virtual-radio provisioning may be necessary, but the patch does not establish whether the triggering actor can perform that setup. No physical hardware is intrinsically required for the demonstrated hwsim failure. This is not a race, and the relevant sequence should be repeatable once a suitable interface and a controllable AP-start failure are available. 4. Primitive and severity interpretation The exact primitive is stale configuration state. `ieee80211_start_ap()` can set `enable_beacon`, `beacon_int`, and SSID state, then return through the error path without restoring them. Later scan processing interprets the interface as beacon-enabled and passes inconsistent state into the driver, resulting in division by zero in hwsim. This is neither active structured-object UAF nor fixed stale storage. No object lifetime ends, no dangling reference is consumed, and no second release or refcount mutation exists. The behavior is therefore CLASS_C invalid-state and crash behavior. The demonstrated consequence is a kernel Oops and associated availability loss. A kernel panic is configuration-dependent. There is no patch-supported exploitation leverage beyond the fault, and no evidence of memory corruption, information disclosure, unauthorized modification, or privilege escalation. ImportantCandidate is NO because no Important-preserving corruption, ownership, lifetime, semantic reinterpretation, or authorization primitive exists. AutoDowngradeAllowed is YES because the remaining security effect is a constrained local control-plane DoS with unresolved but capability-gated reachability. 5. One-sentence report phrase A failed mac80211 AP startup can leave stale beacon state that is later consumed during scanning and causes a divide error and kernel Oops in hwsim, with no demonstrated memory corruption or remote packet trigger. 6. Manual review recommendation NO MANUAL CHECK NEEDED The patch establishes a state-reset defect and crash path but no UAF, OOB write, authorization bypass, shared-backing violation, or unresolved Important-grade exploitation primitive. 7. Call-site confidence Call-site confidence: high ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: mac80211: reset state when starting AP fails [ Upstream Commit: d83da43e9b3b3b1bad99ac5a1065f1c63ad5fc32 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d83da43e9b3b3b1bad99ac5a1065f1c63ad5fc32 Changed files: net/mac80211/driver-ops.c net/mac80211/main.c net/mac80211/offchannel.c net/mac80211/scan.c net/wireless/core.c net/mac80211/cfg.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=d83da43e9b3b3b1bad99ac5a1065f1c63ad5fc32 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98334 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98334 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:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 5.5 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: unknown Paranoid ActionableScore: 1 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: LOW KPANIC detected for this report: NO Published priority for this report (same as in Subject): LOW 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).