From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-64030][IMPORTANT] wifi: mac80211: bounds-check link_id in ieee80211_ml_epcs [ Upstream Date: Sun, 19 Jul 2026 20:35:53 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-64030 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: 7 X-AL-KERNEL-ActionableScore-Lower: 5 X-AL-KERNEL-Commit: 2d8379834800c30602f24c71ab7c40f5fe84d200 List-Id: CVE: CVE-2026-64030 Priority: IMPORTANT AL-KERNEL base severity: IMPORTANT KPANIC flag: YES Patch: wifi: mac80211: bounds-check link_id in ieee80211_ml_epcs [ Upstream Commit: 2d8379834800c30602f24c71ab7c40f5fe84d200 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2d8379834800c30602f24c71ab7c40f5fe84d200 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64030 Analysis date: Sun, 19 Jul 2026 20:35:53 -0400 ActionableScore: 7 ActionableScore lower bound: 5 Actionable bucket: Strong Important candidate / Actionable Moderate at minimum Manual review required: YES Summary: A connected WiFi 7 AP can send an EPCS response with `link_id = 15`, causing mac80211 to read past `sdata->link[]`, interpret adjacent data as a link pointer, and crash the kernel, with limited type-confusion concern requiring manual review. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-64030 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64030 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-2026-64030 IMPORTANT CHECK WITH IMPACT FROM ORIG NN IMPORTANT Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H';CWE-129;CWE-125;**CWE-476;Other CVSS 'AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '7.6';DESCR 'A bounds check bug in mac80211 EPCS handling allows a connected WiFi 7 AP to supply link_id 15 in a PER_STA_PROFILE subelement even though sdata link has valid indices 0 to 14. The out of bounds entry is read as a pointer and can bypass the NULL check because it overlaps initialized activate_links_work data, then ieee80211_sta_wmm_params dereferences the bogus link pointer and crashes the kernel. For the CVSS the PR:N is used for the paranoid score because the attacker does not need privileges on the victim once it can act as the associated AP or control the adjacent WiFi link. The issue is adjacent network reachable rather than Internet reachable. Impact is at least denial of service via kernel crash and worst case may allow limited confidentiality or integrity impact due to type confusion from an out of bounds pointer read, so it should be reviewed manually.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Strong Important candidate / Actionable Moderate at minimum (with actual score 7) YES REMOTE OOB DANGER KERNEL_PANIC_PLUS_UAF KPANIC YES NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=7 ActionableScoreLower=5 ## 1. ActionableScore * Conservative score: 5 * Paranoid score: 7 * Final recommended bucket: **Strong Important candidate / Actionable Moderate at minimum**:: ## 2. Signal breakdown Conservative signals: * Remote reachable / network-triggerable: +2 Trigger is an 802.11 action frame from a connected WiFi 7 AP. This is adjacent-network reachable, not Internet reachable, but still network-triggerable. * Memory corruption, weak/indirect corruption candidate: +1 `link_id = 15` causes an out-of-bounds array read from `sdata->link[]`, interpreted as a pointer. * Reliable kernel crash / strong DoS: +1 The bogus pointer is passed to `ieee80211_sta_wmm_params()` and dereferenced via `link->sdata`, causing kernel crash. * Broad/default/common subsystem exposure: +1 mac80211 is a common Linux WiFi client subsystem, although the exact trigger requires WiFi 7 MLO/EPCS conditions. Paranoid additional signals: * Weak LPE concern: +1 The bug is more than a simple NULL dereference because an out-of-bounds word is interpreted as a kernel object pointer and then dereferenced as a different structure. No reliable write or reclaim primitive is shown. * Confidentiality impact plausible: +1 Limited C impact is plausible only under paranoid interpretation due to invalid object interpretation, not because an info leak is demonstrated. * Integrity impact plausible: +1 Limited I impact is plausible only under paranoid interpretation because type confusion-like pointer use can sometimes become a corruption sink. * Corruption primitive highly constrained / no attacker-controlled payload: -1 The patch shows controlled index selection but not attacker-controlled pointer contents, arbitrary write, callback control, or reclaim. ## 3. Reachability analysis A connected or malicious WiFi 7 AP can trigger the bug by sending an EPCS Enable Response action frame with a `PER_STA_PROFILE` subelement where `link_id = 15`. The victim does not need local privileges, so PR is effectively none for the adjacent-network attacker model. This is not Internet-reachable and requires the attacker to control or impersonate the associated AP, or otherwise operate in the adjacent WiFi environment. Containers and namespaces are not the relevant privilege boundary here because the trigger is in the wireless client receive/control path. ## 4. Severity interpretation This is not an ordinary local Moderate issue because the trigger is adjacent-network reachable and produces a reliable kernel crash. The demonstrated impact is DoS. The theoretical memory-corruption potential is limited but non-zero because the bug performs an out-of-bounds pointer read and then treats adjacent kernel data as a `link` object. There is no demonstrated arbitrary write, controlled object replacement, UAF reclaim, or callback hijack, so the conservative score should not be pushed into Critical-like territory. Paranoid handling as Strong Important candidate is justified for manual review because the bug combines network adjacency, OOB pointer use, and kernel crash in a common wireless subsystem. ## 5. One-sentence report phrase A connected WiFi 7 AP can send an EPCS response with `link_id = 15`, causing mac80211 to read past `sdata->link[]`, interpret adjacent data as a link pointer, and crash the kernel, with limited type-confusion concern requiring manual review. ## 6. Manual review recommendation MANUAL CHECK REQUIRED Reason: adjacent-network trigger plus out-of-bounds pointer interpretation and reliable kernel crash should not be auto-closed, even though practical privilege escalation is not demonstrated. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: mac80211: bounds-check link_id in ieee80211_ml_epcs [ Upstream Commit: 2d8379834800c30602f24c71ab7c40f5fe84d200 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2d8379834800c30602f24c71ab7c40f5fe84d200 Changed files: net/mac80211/mlme.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=2d8379834800c30602f24c71ab7c40f5fe84d200 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-64030 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64030 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:N/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS vector: AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H The Best / paranoid CVSS score: 7.6 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: 7 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).