From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-98705][MODERATE REGULAR] wifi: mac80211: account proxy paths against the mesh path limit Date: Sat, 24 Oct 2026 07:02:28 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-98705 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: unknown X-AL-KERNEL-Commit: df072db65fdaa34ad15e1d66fc06a53e3e97f778 List-Id: CVE: CVE-2026-98705 Priority: MODERATE REGULAR AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: wifi: mac80211: account proxy paths against the mesh path limit Commit: df072db65fdaa34ad15e1d66fc06a53e3e97f778 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=df072db65fdaa34ad15e1d66fc06a53e3e97f778 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98705 Analysis date: Sat, 24 Oct 2026 07:02:28 -0400 ActionableScore: 3 ActionableScore lower bound: unknown Actionable bucket: Borderline / manual review recommended Manual review required: YES Summary: Nearby mesh proxy-path churn can underflow path accounting and bypass the 1024-entry path-table resource limit, potentially increasing memory and CPU consumption without demonstrated memory corruption. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98705 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98705 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-2026-98705 MODERATE https://www.kernelcve.org/list/?q=CVE-2026-98705 CHECK WITH IMPACT FROM ORIG NN MODERATE | AEGIS IMPACT MODERATE_KPANIC AEGIS_AS=1 LEGACY=MODERATE RESULT=DIFF (final Legacy and Aegis differ; FINAL: MODERATE, Aegis: MODERATE_KPANIC) Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H';CWE-682;**CWE-400;CWE-770;Other CVSS 'AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '6.5';DESCR 'Incorrect accounting of the shared mesh path quota lets proxy path removal decrement a counter that was never incremented when the proxy path was added. Repeated proxy path creation and expiration can drive the counter below the real number of installed paths and allow later additions to exceed the 1024 path limit. The demonstrated primitive is resource limit bypass and potential memory or CPU exhaustion. There is no evidence of UAF, OOB access, information disclosure, or an arbitrary write. For the CVSS the PR:N value in the paranoid vector covers an open mesh where a nearby radio attacker can participate without credentials, while PR:L in the base vector represents a protected mesh that requires valid peer access. Automated impact decision path. The original SimpleNet classifier selected MODERATE_KPANIC. The primary LLM estimated paranoid CVSS 6.5 and the production ActionableScore returned 3 with recommendation Borderline / manual review recommended. The production rules then evaluated CVSS thresholds and ActionableScore thresholds. Recorded rule transitions were ActionableScore thresholds stage MODERATE_KPANIC to MODERATE because the ActionableScore threshold rule was applied. The legacy KP specialist has no review artifact for this run. The legacy FD or DH downgrade specialist has no review artifact for this run. Exact triggered rule markers were DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4 and V41_INHERITED_KPANIC_PROMOTION_BLOCKED and MANUAL_REVIEW_REQUIRED. The independent weaker Aegis shadow evaluated CVSS 2.5 and ActionableScore 1 with primitive class CLASS_C and manual review REQUIRED. Its independently reconciled impact was MODERATE_KPANIC. The models disagreed but the aggregation rules retained the production result. The final reported impact is MODERATE.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline / manual review recommended (with actual score 3) MAYBE REMOTE SIMPLEFIX DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4 V41_INHERITED_KPANIC_PROMOTION_BLOCKED MANUAL_REVIEW_REQUIRED - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=3 PrimitiveClass=CLASS_C RealUAF=NO HostAdminRequired=NO NamespaceScopedPrivilege=NO ImportantCandidate=NO ManualReview=RECOMMENDED AutoDowngradeAllowed=YES RequiresHostUID0=NO AuthorizationDecisionBypass=NO ProtectedResourceImpact=NONE B4PendingReview=NO B4PendingConfirmed=NO 1. ActionableScore * Raw base score: 3. * Conservative score: 3; no floor or cap applied. * Raw paranoid score: 3. * Paranoid score: 3; stronger consequences are not sufficiently evidenced. * Final recommended bucket: **Borderline / manual review recommended**:: 2. Signal breakdown * +2 — Adjacent network reachability: supplied evidence grounds repeated proxy-path creation and expiration by a participating nearby mesh peer. * +1 — Concrete resource-limit/accounting bypass: uncharged proxy paths are later decremented, driving `mpaths` below the installed-path count and defeating the shared 1024-entry limit. * +0 — Strong DoS not awarded: memory or CPU exhaustion is plausible, but neither host-wide exhaustion nor a reliable crash is demonstrated. * +0 — No corruption primitive: the changed state is an atomic quota counter; no heap OOB, UAF, invalid pointer, or overwrite is shown. * +0 — No authorization bypass: this is quota enforcement, not a mandatory credential or capability guard changing DENY to ALLOW. * No rarity, timing, or privilege penalty: the evidence does not establish a difficult race, host-admin trigger requirement, or sufficiently rare deployment. NEW52 B5-R does not apply: there is no confirmed heap/slab OOB write or later consumption of OOB-corrupted descriptors. NEW53 and B4-PENDING are also inapplicable. 3. Reachability analysis A nearby mesh participant can influence proxy-path churn after a mesh interface has been configured. An open mesh may permit an unauthenticated radio peer; a protected mesh requires peer credentials, but neither model requires host-administrator powers for the subsequent churn. Initial mesh-interface provisioning is prior host-side setup. No user-namespace or namespace-scoped capability chain is involved, and no special timing race is shown. 4. Primitive and severity reading The exact defect is negative quota accounting: proxy entries consume no slot when added but return a slot when freed. The corrupted counter is later read by `mesh_path_add()`, permitting the installed path count to exceed `MESH_MAX_MPATHS`. This is passive accounting/resource-state corruption, classified CLASS_C. The shown effect is limit bypass and potentially accumulating path-table resource consumption. Host-wide exhaustion, panic, memory corruption, confidentiality loss, integrity compromise, and privilege escalation remain unproven. ImportantCandidate is therefore NO, and ordinary Moderate downgrade remains permissible after review. 5. One-sentence report phrase Nearby mesh proxy-path churn can underflow path accounting and bypass the 1024-entry path-table resource limit, potentially increasing memory and CPU consumption without demonstrated memory corruption. 6. Manual review advice MANUAL CHECK RECOMMENDED Confirm practical path accumulation, cleanup behavior, and whether a reachable workload can cause host-wide resource exhaustion. 7. Call-site confidence Call-site confidence: high ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: mac80211: account proxy paths against the mesh path limit Commit: df072db65fdaa34ad15e1d66fc06a53e3e97f778 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=df072db65fdaa34ad15e1d66fc06a53e3e97f778 Commit description: Proxy-path churn can drive the interface path counter negative and let later mesh path additions exceed MESH_MAX_MPATHS. mesh_path_free_rcu() decrements the interface mpaths counter for entries from both the mesh and proxy path tables, but mpp_path_add() never reserves a slot in that counter. Removing or expiring a proxy path therefore returns a slot that was never charged. mesh_path_add() uses the same counter to enforce MESH_MAX_MPATHS, so once it falls below the number of installed paths the limit no longer holds. Reserve the shared quota before allocating a proxy path and release it on every unsuccessful addition. Mesh and proxy paths now share one 1024-entry budget, so mpp_path_add() can return -ENOSPC at that limit. Fixes: ece1a2e ("mac80211: Remove mesh paths when an interface is removed") Cc: stable@vger.kernel.org Assisted-by: LLM sparse kasan Signed-off-by: Zhao Li Link: https://patch.msgid.link/20260916113649.28315-3-enderaoelyther@gmail.com Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman Changed files: net/mac80211/mesh_pathtbl.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=df072db65fdaa34ad15e1d66fc06a53e3e97f778 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98705 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98705 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:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L The Best / paranoid CVSS vector: AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 6.5 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: 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).