From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-93094][MODERATE 7.0] wifi: ath12k: fix dp_link_peer dangling references on AP vdev rollback [ Upstream Date: Fri, 18 Sep 2026 02:33:52 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-93094 X-AL-KERNEL-Priority: MODERATE 7.0 X-AL-KERNEL-Severity: MODERATE 7.0 X-AL-KERNEL-Base-Severity: MODERATE X-AL-KERNEL-KPANIC: YES X-AL-KERNEL-ActionableScore: 6 X-AL-KERNEL-ActionableScore-Lower: 5 X-AL-KERNEL-Commit: af405d216316d99f9b48733145fc708110011e0f List-Id: CVE: CVE-2026-93094 Priority: MODERATE 7.0 AL-KERNEL base severity: MODERATE KPANIC flag: YES Patch: wifi: ath12k: fix dp_link_peer dangling references on AP vdev rollback [ Upstream Commit: af405d216316d99f9b48733145fc708110011e0f Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=af405d216316d99f9b48733145fc708110011e0f Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93094 Analysis date: Fri, 18 Sep 2026 02:33:52 -0400 ActionableScore: 6 ActionableScore lower bound: 5 Actionable bucket: Actionable Moderate / Strong Important candidate requiring manual review Manual review required: YES Summary: No one-sentence report phrase was found. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-93094 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93094 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 7.0 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-2026-93094 MODERATE https://www.kernelcve.org/list/?q=CVE-2026-93094 CHECK WITH IMPACT FROM ORIG NN MODERATE 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-825;*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 use after free condition can occur in the ath12k AP vdev rollback path because dp_link_peer remains published in the RCU peer table, the dp_peer link_peers array, and the per address rhashtable after the object is freed by the unmap event. Later peer lookups can dereference stale pointers and may crash the kernel. For the CVSS the PR:L is used for the paranoid score because reliable triggering normally requires local control over AP or vdev setup, but this control may be delegated to a network management service, container, or reduced capability account rather than full host root. The issue is not directly network reachable as an initial trigger, although wireless traffic or later driver activity may exercise the stale references once the bad rollback state exists. Impact is at least local denial of service via kernel crash. In worst case it may allow confidentiality or integrity impact due to kernel UAF style memory corruption and should be reviewed manually.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Actionable Moderate / Strong Important candidate requiring manual review (with actual score 6) SKIP CVE-2026-93094 UNKNOWN SKIP The Fixes patch not applied yet, so unlikely that actual: url YES NO NO unknown MAYBE REMOTE DANGER INIT UAF NETWORK LINUS KPANIC KPANIC INCREASED_TO_HIGH_BASED_ON_GUESSCVSS DECREASED_TO_MODERATE7_BASED_ON_FALSEPOSCHECKOFDH - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=6 ActionableScoreLower=5 PrimitiveClass=CLASS_B RealUAF=YES HostAdminRequired=UNKNOWN NamespaceScopedPrivilege=UNKNOWN ImportantCandidate=YES ManualReview=REQUIRED AutoDowngradeAllowed=NO 1. ActionableScore * Raw conservative score: 4 * Conservative score: 5 * Raw paranoid score: 6 * Paranoid score: 6 * Final recommended bucket: **Actionable Moderate / Strong Important candidate requiring manual review**:: Conservative floor applied: 4 -> 5 because this is a real active-object UAF where stale references remain published in RCU and hash lookup structures and later lookups may consume the freed object. No cap was applied. 2. Signal breakdown Conservative signals: * +2 Real UAF / active lifetime violation: dp_link_peer is published in dp_hw->dp_peers, dp_peer->link_peers, and the per-address rhashtable, then freed by the unmap event without first being unpublished. * +1 Reliable kernel crash / strong DoS: later lookups may dereference the dangling dp_link_peer pointer and crash the kernel. * +1 Secondary index / lookup staleness: the vulnerable path leaves stale entries in active lookup structures, not just passive metadata. * +0 Remote reachability not awarded: the initial trigger is AP vdev rollback/control-plane setup, not attacker packet traffic alone. * +0 Local unprivileged trigger not awarded: ordinary unprivileged reachability is not established. * +0 Host-admin penalty not applied: host-admin-equivalent privilege is not positively established from the supplied evidence. * +0 Race penalty not applied: the bug is an ordered rollback/unpublish lifetime error, not a proven hard timing race. * +0 Hardware penalty not applied: ath12k hardware is required, but the evidence does not establish rare or physical-only attacker access as the controlling limitation. Paranoid additional signals: * +1 Structured stale-object exploitation leverage: the freed dp_link_peer remains reachable through active RCU and rhashtable lookup paths, so later kernel processing may consume stale structured peer state rather than only faulting in a local destructor. * +1 Attacker-influenced active-object lifetime concern: a local actor able to drive AP vdev creation and rollback can influence creation and removal of the affected peer object, although controlled reclaim is not demonstrated. Important non-awarded signals: * Controlled reclaim is not demonstrated. * Arbitrary or directed kernel write is not demonstrated. * Callback or function-pointer control is not demonstrated. * Confidentiality and integrity are not scored as established impacts in the conservative score. * C/I are not awarded merely because a UAF could theoretically corrupt reclaimed memory. * Concrete repeated release/refcount signal is not awarded. The patch establishes stale published references and later stale lookup use, but not a second concrete put/release/refcount mutation on the exact same dangling reference. * Paranoid repeated-refcount leverage is not awarded. * Extra availability is not awarded because the same kernel crash is already counted once. * Weak LPE is not separately awarded beyond the paranoid structured stale-object concern. Repeated release/refcount checklist: * First release can end lifetime: yes, dp_link_peer can be freed by ath12k_dp_link_peer_unmap_event. * Exact same reference survives: yes, stale references remain in RCU table, link_peers array, and rhashtable. * Second operation is a real lifetime/refcount mutation: not established. * Concrete repeated release/refcount +1 awarded: no. * Paranoid repeated-refcount leverage +1 awarded: no. * FLOOR 5 applied: yes, but due active stale lookup surface, not due repeated release/refcount. 3. Reachability analysis The direct trigger is local control-plane activity that creates an AP vdev on ath12k. That normally implies wireless management privileges such as CAP_NET_ADMIN or a privileged network management service, but the supplied evidence does not prove that full host-admin-equivalent privilege is always required. HostAdminRequired is therefore UNKNOWN. NamespaceScopedPrivilege is also UNKNOWN because the complete AP vdev creation, rollback, device ownership, and ath12k hardware control chain is not shown to be fully namespace-scoped. A prior physical ath12k-capable device and driver support are required. This is hardware-specific, but not enough by itself to apply a rare-hardware penalty. The issue is not directly network-triggerable as an initial entry point. Wireless traffic or later driver activity may exercise the stale references after the bad rollback state has been created. The bug is not primarily a timing race. The relevant sequence is peer creation, later failure, rollback through an open-coded peer delete path, free by unmap event, and stale published references remaining for later lookup. 4. Primitive and severity interpretation The exact primitive is a real kernel use-after-free / dangling-reference condition. The stale object is an active structured ath12k dp_link_peer, not fixed stale storage. It remains reachable through active lookup structures including an RCU peer table and rhashtable. This is broader than an ordinary cleanup-only stale dereference because the freed object remains published for later lookup operations. However, the supplied evidence does not establish controlled reclaim, attacker-shaped replacement contents, arbitrary read/write, callback control, or demonstrated privilege escalation. PrimitiveClass is CLASS_B. The demonstrated consequence is kernel crash / DoS. The speculative consequence is stronger exploitation from stale structured peer lookup, but that remains unresolved and requires manual review. ImportantCandidate is YES because this is a real active-object UAF with stale references left in live lookup structures, and exploitation leverage beyond crash is not fully resolved. AutoDowngradeAllowed is NO because automatically closing this as ordinary Moderate would discard a concrete kernel lifetime primitive with meaningful unresolved stale-object lookup surface. Operationally, this is at least Actionable Moderate. It is not proven Strong Important, but it is a strong manual-review candidate. 5. One-sentence report phrase A real ath12k dp_link_peer use-after-free can occur on AP vdev rollback because published RCU and hash-table references are left pointing to an object freed by the peer unmap event, allowing later lookups to dereference stale kernel state and crash the system. 6. Manual review recommendation MANUAL CHECK REQUIRED Reason: real active-object UAF with stale references in RCU and rhashtable lookup structures. Controlled exploitation is not proven, but the primitive should not be automatically downgraded to ordinary crash-only behavior. 7. Call-site confidence Call-site confidence: high ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: ath12k: fix dp_link_peer dangling references on AP vdev rollback [ Upstream Commit: af405d216316d99f9b48733145fc708110011e0f Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=af405d216316d99f9b48733145fc708110011e0f Changed files: drivers/net/wireless/ath/ath12k/mac.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=af405d216316d99f9b48733145fc708110011e0f ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-93094 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93094 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: 5 Paranoid ActionableScore: 6 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: YES Published priority for this report (same as in Subject): MODERATE 7.0 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).