From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-46152][IMPORTANT] wifi: mac80211: drop stray 'static' from fast-RX rx_result Date: Thu, 28 May 2026 12:11:12 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-46152 X-AL-KERNEL-Priority: IMPORTANT X-AL-KERNEL-Severity: IMPORTANT X-AL-KERNEL-Base-Severity: IMPORTANT X-AL-KERNEL-KPANIC: YES X-AL-KERNEL-ActionableScore: 8 X-AL-KERNEL-ActionableScore-Lower: 5 X-AL-KERNEL-Commit: 03584528bfffb195e384698af9148b94e42e3f14 List-Id: CVE: CVE-2026-46152 Priority: IMPORTANT AL-KERNEL base severity: IMPORTANT KPANIC flag: YES Patch: wifi: mac80211: drop stray 'static' from fast-RX rx_result Commit: 03584528bfffb195e384698af9148b94e42e3f14 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=03584528bfffb195e384698af9148b94e42e3f14 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-46152 Analysis date: Thu, 28 May 2026 12:11:12 -0400 ActionableScore: 8 ActionableScore lower bound: 5 Actionable bucket: Strong Important candidate / Actionable Moderate at minimum Manual review required: YES Summary: mac80211 fast RX used a shared static `rx_result`, allowing concurrent RX callers to corrupt each other decisions and potentially double-process an already consumed skb in Wi-Fi mesh fast-RX. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-46152 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-46152 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: IMPORTANT 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-2026-46152 IMPORTANT CHECK Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H';CWE-362;*CWE-416;CWE-667;*CWE-664;Other CVSS 'AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H';BEST CVSS score: '7.5';DESCR 'mac80211 fast RX used a static rx_result variable inside ieee80211_invoke_fast_rx, so concurrent RX callers could overwrite each other result. This can make a packet already queued or consumed by ieee80211_rx_mesh_data continue into ieee80211_rx_8023, or make a packet that should continue return as queued. For the CVSS the PR:N is used because an RF adjacent peer may trigger parallel RX traffic without local privileges on the victim once mesh fast RX is active. The issue is not Internet reachable and requires a specific Wi-Fi mesh fast RX race condition. Impact is at least denial of service through kernel crash or packet processing corruption, and worst case may allow confidentiality or integrity impact because double processing of consumed skb data can become a kernel lifetime corruption issue.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Strong Important candidate / Actionable Moderate at minimum (with actual score 7) MAYBE REMOTE SIMPLEFIX KPANIC PACKET KPANIC INCREASED_TO_HIGH_BASED_ON_GUESSCVSS - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=8 ActionableScoreLower=5 ## 1. ActionableScore * Conservative score: 5 * Paranoid score: 8 * Final recommended bucket: **Strong Important candidate / Actionable Moderate at minimum**:: ## 2. Signal breakdown Conservative signals: * Firmware/RF-mediated external influence: +1. An RF-adjacent peer can contribute traffic that reaches the Wi-Fi mesh fast-RX path. * Reliable kernel crash / strong DoS: +1. Incorrect RX result sharing can cause packets to be misprocessed and may crash or destabilize mac80211. * Common networking packet-processing path: +1. mac80211 RX processing is a core Wi-Fi packet path. * Availability impact realistic: +1. Packet processing corruption can break connectivity or cause kernel failure. * Integrity impact plausible: +1. The wrong per-packet decision can cause incorrect packet handling, including processing a packet that was already consumed. * Hard/racy condition: -1. The issue requires concurrent RX callers and a race window. Paranoid additional signals: * Generic memory corruption: +2. Continuing with an skb after it was queued or consumed can plausibly become use-after-free or lifetime corruption. * Real lifetime corruption: +1. The affected object is per-packet processing state, and stale/shared results can cause double processing of consumed skb state. * Weak to strong LPE concern: +1. skb lifetime corruption in a kernel networking path can sometimes be exploitable, though no concrete primitive is shown. ## 3. Reachability analysis The issue is RF-adjacent, not Internet-reachable. An attacker in radio range may generate traffic that increases parallel RX activity once the victim is using Wi-Fi mesh fast-RX. Practical exploitation requires mesh fast-RX support, concurrent packet processing, and a timing window where the shared static `rx_result` is overwritten between `ieee80211_rx_mesh_data()` and the switch on the result. Local privileges are not required for the RF-adjacent trigger, but configuration of mesh mode is an environmental precondition. ## 4. Severity interpretation This is at least actionable Moderate and a Strong Important candidate under paranoid triage. The realistic impact is packet-processing corruption or DoS. The higher concern is possible skb lifetime corruption if an already queued or consumed packet is processed again. The patch does not show a demonstrated arbitrary write or LPE chain, so the Important classification is a manual-review candidate rather than proven exploitation. ## 5. One-sentence report phrase mac80211 fast RX used a shared static `rx_result`, allowing concurrent RX callers to corrupt each other decisions and potentially double-process an already consumed skb in Wi-Fi mesh fast-RX. ## 6. Manual review recommendation MANUAL CHECK REQUIRED This is an RF-adjacent race in a packet-processing path with plausible skb lifetime corruption. Practical severity depends on mesh fast-RX exposure and race reliability. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: mac80211: drop stray 'static' from fast-RX rx_result Commit: 03584528bfffb195e384698af9148b94e42e3f14 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=03584528bfffb195e384698af9148b94e42e3f14 Commit description: ieee80211_invoke_fast_rx() is documented as safe for parallel RX, but its per-invocation rx_result is declared static. Concurrent callers then share one instance and can overwrite each other's result between ieee80211_rx_mesh_data() and the switch on res. That can make a packet that was queued or consumed by ieee80211_rx_mesh_data() fall through into ieee80211_rx_8023(), or make a packet that should continue return as queued. Make res an automatic variable so each invocation keeps its own result. Fixes: 3468e1e ("wifi: mac80211: add mesh fast-rx support") Cc: stable@vger.kernel.org Signed-off-by: Catherine Link: https://patch.msgid.link/20260424131435.83212-2-enderaoelyther@gmail.com Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman Changed files: net/mac80211/rx.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=03584528bfffb195e384698af9148b94e42e3f14 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-46152 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-46152 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:N/UI:N/S:U/C:N/I:L/A:H The Best / paranoid CVSS vector: AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H The Best / paranoid CVSS score: 7.5 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: 5 Paranoid ActionableScore: 8 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: IMPORTANT KPANIC detected for this report: YES Published priority for this report (same as in Subject): IMPORTANT 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).