From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-98701][MODERATE REGULAR] wifi: mac80211: release mesh path quota on failed additions Date: Sat, 24 Oct 2026 12:53:13 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-98701 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: 2 X-AL-KERNEL-Commit: 56691ed9ef792f180e008a43294a4dc059fbeca2 List-Id: CVE: CVE-2026-98701 Priority: MODERATE REGULAR AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: wifi: mac80211: release mesh path quota on failed additions Commit: 56691ed9ef792f180e008a43294a4dc059fbeca2 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=56691ed9ef792f180e008a43294a4dc059fbeca2 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98701 Analysis date: Sat, 24 Oct 2026 12:53:13 -0400 ActionableScore: 4 ActionableScore lower bound: 2 Actionable bucket: Borderline / manual review recommended Manual review required: YES Summary: Repeated failed or duplicate mac80211 mesh-path additions leak path quota and can block later route creation without showing memory corruption or host-wide failure. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98701 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98701 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-2026-98701 MODERATE https://www.kernelcve.org/list/?q=CVE-2026-98701 CHECK WITH IMPACT FROM ORIG NN MODERATE | AEGIS IMPACT MODERATE AEGIS_AS=1 LEGACY=MODERATE RESULT=SAME (final reconciliation agrees; DECISION: both MODERATE) 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:L';*CWE-772;**CWE-400;CWE-404;Other CVSS 'AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.3';DESCR 'mac80211 mesh path accounting reserves quota before allocation and rhashtable insertion but did not return that quota when allocation failed or when insertion returned an error or an existing destination. Repeated failures or duplicate additions can make the mpaths counter reach MESH_MAX_MPATHS while the table contains fewer paths, preventing creation of paths to newly reachable destinations. For the CVSS the PR:N value in the paranoid vector is defensible for an open mesh where an adjacent radio peer can influence path discovery without prior authorization. Reliable attacker control is not established by the patch and secured mesh deployments can require membership credentials. The demonstrated primitive is persistent quota retention with limited mesh availability impact. There is no evidence of UAF, out of bounds access, information disclosure, kernel panic, or host wide resource exhaustion. Automated impact decision path. The original SimpleNet classifier selected MODERATE_KPANIC. The primary LLM estimated paranoid CVSS 4.3 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 CVSS and initial triage stage MODERATE_KPANIC to MODERATE because the CVSS score, vector or bug class 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_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS. The independent weaker Aegis shadow evaluated CVSS 2.7 and ActionableScore 1 with primitive class CLASS_C and manual review REQUIRED. Its independently reconciled impact was MODERATE. The shadow agreed with the final production impact and aggregation did not change that impact. The final reported impact is MODERATE.';NO MANUAL CHECK; ,and ActionableScore result is Borderline / manual review recommended (with actual score 3) MAYBE REMOTE SIMPLEFIX DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=4 ActionableScoreLower=2 PrimitiveClass=CLASS_C RealUAF=NO HostAdminRequired=UNKNOWN NamespaceScopedPrivilege=UNKNOWN ImportantCandidate=NO ManualReview=RECOMMENDED AutoDowngradeAllowed=YES RequiresHostUID0=UNKNOWN AuthorizationDecisionBypass=NO ProtectedResourceImpact=NONE B4PendingReview=NO B4PendingConfirmed=NO 1. ActionableScore * Raw base score: 2. * Conservative score: 2; no floor or cap applied. * Raw paranoid score: 4. * Paranoid score: 4; no floor or cap applied. * Final recommended bucket: **Borderline / manual review recommended**:: 2. Signal breakdown * +1 concrete persistent resource/quota leak: `mpaths` is incremented before allocation/insertion and was not decremented when no path was installed. * +1 availability impact: accumulated reservations can reach `MESH_MAX_MPATHS` and prevent creation of paths to newly reachable destinations. * Paranoid +2 network reachability: an adjacent peer in an open mesh can plausibly influence repeated path discovery or duplicate additions. This is deployment-dependent and not established by the patch, so it is excluded from the conservative score. * No UAF, OOB access, memory overwrite, authorization bypass, disclosure, kernel crash, or host-wide exhaustion is shown. * The resource defect and resulting mesh-path denial are counted separately, but no additional generic exhaustion or crash point is awarded. 3. Reachability analysis The vulnerable operation occurs in mac80211 mesh path creation. A configured mesh interface and wireless hardware are prerequisites. In an open mesh, an adjacent radio peer may be able to influence path additions without local privilege; secured meshes may require membership credentials. The supplied evidence does not establish who can force allocation failure or reliably generate the necessary duplicate/error sequence. The initial mesh-interface configuration may require privileged setup, but that does not prove every later packet-driven trigger requires host administration. Conversely, complete below-host-admin triggering is not proven. Capability namespace scope is also not shown. No timing race is required. 4. Primitive and severity reading The primitive is persistent mesh-path quota-accounting leakage: failed candidates consume logical capacity despite never entering the table. This is passive invalid state producing interface-level availability loss, hence CLASS_C. It is not a lifetime violation or retry-accumulated OOB write, and corrupted structured state is not consumed in a dangerous later kernel operation. ImportantCandidate is NO because impact is confined to mesh route creation and no corruption or trust-boundary primitive remains. AutoDowngradeAllowed is YES. 5. One-sentence report phrase Repeated failed or duplicate mac80211 mesh-path additions leak path quota and can block later route creation without showing memory corruption or host-wide failure. 6. Manual review advice MANUAL CHECK RECOMMENDED Confirm whether an unauthenticated adjacent mesh peer can reliably drive the failure or duplicate-addition sequence in affected deployments. 7. Call-site confidence Call-site confidence: medium ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: mac80211: release mesh path quota on failed additions Commit: 56691ed9ef792f180e008a43294a4dc059fbeca2 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=56691ed9ef792f180e008a43294a4dc059fbeca2 Commit description: Repeated failed or duplicate mesh path additions can exhaust MESH_MAX_MPATHS while the path table holds fewer paths, which stops new paths to reachable destinations from being created. mesh_path_add() reserves a slot before allocating and inserting a path. If allocation fails, the function returns without releasing the slot. If the rhashtable insertion reports an error or an existing destination, the function discards its candidate but retains the reservation. No new path is installed in any of these cases. Release the reservation whenever the candidate is not installed. Fixes: ae76eef ("mac80211: return new mpath from mesh_path_add()") Fixes: 60854fd ("mac80211: mesh: convert path table to rhashtable") Cc: stable@vger.kernel.org Assisted-by: LLM sparse kasan Signed-off-by: Zhao Li Link: https://patch.msgid.link/20260916113649.28315-2-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=56691ed9ef792f180e008a43294a4dc059fbeca2 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98701 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98701 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:H/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:L The Best / paranoid CVSS score: 4.3 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: 2 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).