From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-98341][MODERATE REGULAR] wifi: cfg80211: don't free driver-owned scan requests [ Upstream Date: Sat, 10 Oct 2026 07:55:49 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-98341 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: 4 X-AL-KERNEL-ActionableScore-Lower: unknown X-AL-KERNEL-Commit: e8c75736cfd0c6c87562cda2312e3fe5e2227955 List-Id: CVE: CVE-2026-98341 Priority: MODERATE REGULAR AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: wifi: cfg80211: don't free driver-owned scan requests [ Upstream Commit: e8c75736cfd0c6c87562cda2312e3fe5e2227955 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=e8c75736cfd0c6c87562cda2312e3fe5e2227955 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98341 Analysis date: Sat, 10 Oct 2026 07:55:49 -0400 ActionableScore: 4 ActionableScore lower bound: unknown Actionable bucket: Borderline / manual review recommended Manual review required: YES Summary: No one-sentence report phrase was found. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98341 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98341 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-2026-98341 MODERATE https://www.kernelcve.org/list/?q=CVE-2026-98341 CHECK WITH IMPACT FROM ORIG NN LOW | AEGIS IMPACT MODERATE_KPANIC AEGIS_AS=4 LEGACY=MODERATE RESULT=DIFF (independent Legacy and Aegis differ; FINAL: MODERATE, Aegis: MODERATE_KPANIC) 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-416;CWE-362;*CWE-672;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '7';DESCR 'A race in cfg80211 scan cancellation can free a scan request while the wireless driver still owns and may later use the same request. When an interface goes down during an active scan, cfg80211 can complete the request toward userspace and release it before the asynchronous driver cancellation has finished. A later cfg80211_scan_done() callback can then access the freed cfg80211_scan_request_int object, resulting in a use-after-free and at least a kernel crash or local denial of service. For the CVSS the PR:L is used for the paranoid score because a container root user, network namespace administrator, or service with delegated CAP_NET_ADMIN may control scans and interface state without having full host privileges. AC:H is appropriate because successful triggering depends on winning the timing window between interface shutdown, request release, and delayed driver completion. The issue is not directly network reachable because receiving wireless traffic alone is not shown to trigger the vulnerable lifetime sequence. In the worst still defensible case, controlled reuse of the freed object could affect confidentiality and integrity or support privilege escalation, but this requires manual verification of allocator control and subsequent accesses.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline / manual review recommended (with actual score 4) MAYBE REMOTE LEAK UAF HARDWARE SYZBOT INCREASED_TO_MODERATE7_FROM_LOW_BASED_ON_GUESSCVSS_AND_ACTIONABLESCOREHIGHER4 DECREASED_TO_MODERATEREG_BASED_ON_FALSEPOSCHECKOFKP - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=4 PrimitiveClass=CLASS_B RealUAF=YES HostAdminRequired=UNKNOWN NamespaceScopedPrivilege=UNKNOWN ImportantCandidate=NO ManualReview=RECOMMENDED AutoDowngradeAllowed=YES RequiresHostUID0=UNKNOWN AuthorizationDecisionBypass=NO ProtectedResourceImpact=NONE B4PendingReview=NO B4PendingConfirmed=NO 1. ActionableScore * Raw conservative score: 3 * Conservative score: 4 * Raw paranoid score: 3 * Paranoid score: 4 * Applied conservative floor: 3 -> 4 under REAL UAF FLOOR 4 because a dynamically allocated structured request is actually used after free and host-admin-equivalent privilege is not positively established. * Applied paranoid floor: 3 -> 4 for the same reason. No additional paranoid leverage point is technically supported. * Final recommended bucket: **Borderline / manual review recommended**:: 2. Signal breakdown Positive signals: * +2 Real UAF / active lifetime violation. `___cfg80211_scan_done()` frees a scan request while the driver can still own it, and a later `cfg80211_scan_done()` callback accesses that request. * +1 Realistic kernel crash / DoS. The stale callback dereferences a freed structured object, making an Oops, KASAN failure, or kernel crash realistic. * No separate Availability point was awarded because it would duplicate the same UAF crash. Negative signals: * No negative points. Host-admin privilege, narrow timing, rare hardware, and difficult reachability are not positively established. * No race penalty. Asynchronous cancellation is intentional architecture, and the commit says the problematic ordering is not avoidable. It does not establish a narrow or externally uncontrollable one-shot race. Important non-awarded signals: * Controlled reclaim or attacker-shaped replacement contents are not demonstrated. * Arbitrary or directed kernel read/write is not demonstrated. * Structured stale-object leverage is not awarded because no meaningful post-reuse pointer, callback, offset, ownership, or refcount consumption is established. * Attacker-influenced repeatable lifetime manipulation is not awarded because control of the complete scan plus interface-down sequence below host-admin privilege is unresolved. * No concrete repeated release/refcount operation is established. The first `kfree()` can end lifetime and the exact stale pointer later survives into the driver callback, but the demonstrated stale operation is a dereference rather than a second put, free, or refcount mutation. * Concrete repeated release/refcount +1 was not awarded. * Paranoid repeated-refcount leverage +1 was not awarded. * FLOOR 5 was not applied. * Confidentiality, integrity, LPE, and remote reachability are not established. * B5-R does not apply because no retry-accumulated OOB write exists. * B3-PENDING does not apply because no shared-backing write exists. * B4-PENDING does not apply because no authorization decision is changed from DENY to ALLOW. 3. Reachability analysis The trigger requires an active cfg80211 scan followed by interface shutdown or P2P-device stopping before the driver reports asynchronous completion. The supplied patch does not establish whether one below-host-admin actor can perform the complete sequence. Scan initiation and interface-state changes commonly involve nl80211 and CAP_NET_ADMIN, but the evidence does not identify the exact capability checks, governing user namespace, device ownership, or whether a physical wireless interface can be fully controlled from an attacker-created namespace. Therefore, `HostAdminRequired` and `NamespaceScopedPrivilege` remain `UNKNOWN`, with no privilege bonus or penalty. No direct packet-triggered or radio-triggered path is established. Wireless hardware or an equivalent test driver is required, but this is not sufficient for a rare-hardware penalty. The asynchronous ordering appears repeatable in normal cancellation architecture, so no hard-race penalty is justified. 4. Primitive and severity interpretation The exact primitive is a heap use-after-free of `struct cfg80211_scan_request_int`. cfg80211 releases the request during interface teardown while the driver retains ownership, after which the driver invokes `cfg80211_scan_done()` with the stale request. This is an active structured object rather than fixed DMA storage. However, the supplied stale path only establishes access to the freed request during asynchronous completion. It does not establish controlled replacement, callback hijacking, arbitrary access, disclosure, a second lifetime mutation, or another independently useful exploitation primitive. This is therefore CLASS_B, but currently a constrained crash-capable asynchronous lifetime bug rather than a strong Important-preserving UAF. The demonstrated consequence is local kernel DoS. Privilege escalation remains theoretical and unsupported by a concrete reuse mechanism. `ImportantCandidate=NO` because meaningful leverage beyond the stale dereference is not established. `AutoDowngradeAllowed=YES` because there is no unresolved repeated refcount mutation, controlled reclaim, authorization bypass, or security-boundary primitive. Manual review remains recommended due to the real heap UAF and unresolved trigger privilege. 5. One-sentence report phrase A cfg80211 ownership race can free an active scan request before asynchronous driver completion, causing a later `cfg80211_scan_done()` callback to access freed heap memory and potentially crash the kernel. 6. Manual review recommendation MANUAL CHECK RECOMMENDED The UAF is concrete, but the supplied evidence supports crash or DoS only and does not establish controlled reuse, a second lifetime mutation, below-host-admin reachability, or an Important-grade exploitation primitive. 7. Call-site confidence Call-site confidence: high ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: cfg80211: don't free driver-owned scan requests [ Upstream Commit: e8c75736cfd0c6c87562cda2312e3fe5e2227955 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=e8c75736cfd0c6c87562cda2312e3fe5e2227955 Changed files: net/wireless/core.c net/wireless/core.h net/wireless/rdev-ops.h net/wireless/scan.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=e8c75736cfd0c6c87562cda2312e3fe5e2227955 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98341 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98341 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:N/I:N/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: unknown Paranoid ActionableScore: 4 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).