From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-98346][LOW] wifi: cfg80211: don't get the radio mask for netdev-less wdevs [ Upstream Date: Sat, 10 Oct 2026 09:57:12 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-98346 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: 5b313159c970e945ee125ca87fad0d96ed913e55 List-Id: CVE: CVE-2026-98346 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: wifi: cfg80211: don't get the radio mask for netdev-less wdevs [ Upstream Commit: 5b313159c970e945ee125ca87fad0d96ed913e55 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5b313159c970e945ee125ca87fad0d96ed913e55 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98346 Analysis date: Sat, 10 Oct 2026 09:57:12 -0400 ActionableScore: 1 ActionableScore lower bound: unknown Actionable bucket: Ordinary Moderate Manual review required: NO Summary: A local cfg80211 control-plane operation can pass a NULL netdev from a netdev-less wireless device into mac80211 and crash the kernel, but no UAF, write primitive, remote trigger, or authorization bypass is established. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98346 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98346 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-2026-98346 LOW https://www.kernelcve.org/list/?q=CVE-2026-98346 CHECK WITH IMPACT FROM ORIG NN MODERATE | AEGIS IMPACT MODERATE_KPANIC AEGIS_AS=1 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-476;*CWE-20;CWE-754;BEST CVSS score: '5.5';DESCR 'A NULL pointer dereference in cfg80211_calculate_bi_data can occur because rdev_get_radio_mask is called with wdev netdev before netdev-less wireless devices are excluded. A local actor able to create or reconfigure the relevant wireless interface state can reach the interface combination validation path and cause mac80211 to dereference the NULL netdev, resulting in a kernel crash and denial of service. For the CVSS the PR:L value is used because triggering normally requires CAP_NET_ADMIN or equivalent delegated control over wireless interfaces, but does not necessarily require unrestricted host root access. The issue is not directly reachable through received WiFi traffic or a remote network connection because the affected path belongs to the cfg80211 control plane. The demonstrated impact is availability loss only, with no source evidence of a UAF, out of bounds access, information disclosure, or write primitive.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1) MAYBE REMOTE DANGER SIMPLEFIX 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 crash / strong DoS. The commit directly states that passing a NULL `wdev->netdev` to `rdev_get_radio_mask()` crashes in mac80211. * +0 Weak corruption concern. The established primitive is a NULL-pointer dereference, not an independently useful memory-corruption operation. Negative signals: * No negative points. Host-admin privilege, namespace-scoped reachability, rare hardware, and difficult timing are not sufficiently established to justify penalties. Material non-awarded signals: * No UAF, OOB read, OOB write, stale lifetime operation, or repeated refcount mutation is established. * Controlled reclaim, arbitrary write, information disclosure, and privilege escalation are not demonstrated. * Remote reachability is not established. Received WiFi traffic does not directly reach the shown cfg80211 control-plane operation. * No extra Availability point is awarded because it would double-count the same kernel crash. * B5-R does not apply because there is no retry-accumulated heap OOB write. * B3-PENDING does not apply because no shared-backing write exists. * B4-PENDING does not apply because no authorization decision or mandatory security guard is bypassed. ## 3. Reachability analysis The vulnerable path is reached while cfg80211 validates wireless interface combinations and processes a netdev-less `wireless_dev`. A local control-plane actor able to create or reconfigure the relevant wireless state is the plausible trigger. Such operations commonly involve `nl80211` and `CAP_NET_ADMIN`, but the supplied patch does not show the complete caller, capability check, governing user namespace, or whether every required stage works with a delegated namespace capability. Therefore: * host-admin-equivalent privilege is not positively established; * below-host-admin complete reachability is not positively established; * complete namespace-scoped triggering is not established; * numeric host UID 0 is not established as mandatory; * no privilege bonus or penalty is applied. A compatible cfg80211/mac80211 wireless device or test device must exist, but the evidence does not justify a rare-hardware penalty. No race or narrow timing window is involved. Packet reception alone is not a demonstrated trigger. ## 4. Primitive and severity interpretation The exact primitive is an invalid NULL argument passed from `cfg80211_calculate_bi_data()` to `rdev_get_radio_mask()`, followed by a NULL dereference in mac80211. This is Class C crash behavior. There is no freed object or stale post-lifetime reference, so `RealUAF=NO`. There is also no repeated release, active structured-object reuse, corrupted descriptor consumption, authorization bypass, or write primitive. The demonstrated consequence is a kernel crash and local denial of service. Stronger confidentiality, integrity, or privilege-escalation consequences are unsupported. `ImportantCandidate=NO` and `AutoDowngradeAllowed=YES` because no unresolved corruption or security-boundary primitive would be lost by ordinary Moderate treatment. ## 5. One-sentence report phrase A local cfg80211 control-plane operation can pass a NULL netdev from a netdev-less wireless device into mac80211 and crash the kernel, but no UAF, write primitive, remote trigger, or authorization bypass is established. ## 6. Manual review recommendation NO MANUAL CHECK NEEDED The patch establishes a direct NULL-pointer crash with availability-only impact and no evidence of an independently useful corruption or security-boundary primitive. ## 7. Call-site confidence Call-site confidence: high ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: cfg80211: don't get the radio mask for netdev-less wdevs [ Upstream Commit: 5b313159c970e945ee125ca87fad0d96ed913e55 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5b313159c970e945ee125ca87fad0d96ed913e55 Changed files: net/wireless/util.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=5b313159c970e945ee125ca87fad0d96ed913e55 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98346 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98346 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: Not available 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).