From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-64515][MODERATE 7.0] wifi: mac80211: fix MLE defragmentation [ Upstream Date: Sat, 25 Jul 2026 15:14:48 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-64515 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: 5 X-AL-KERNEL-ActionableScore-Lower: 4 X-AL-KERNEL-Commit: 1f573e17bcb7275ddd1c8f47f46ae0faf0e902a4 List-Id: CVE: CVE-2026-64515 Priority: MODERATE 7.0 AL-KERNEL base severity: MODERATE KPANIC flag: YES Patch: wifi: mac80211: fix MLE defragmentation [ Upstream Commit: 1f573e17bcb7275ddd1c8f47f46ae0faf0e902a4 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1f573e17bcb7275ddd1c8f47f46ae0faf0e902a4 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64515 Analysis date: Sat, 25 Jul 2026 15:14:48 -0400 ActionableScore: 5 ActionableScore lower bound: 4 Actionable bucket: Actionable Moderate at minimum Manual review required: YES Summary: A crafted adjacent WiFi management frame can cause mac80211 MLE defragmentation to use mismatched element and container bounds, potentially leading to a bounded heap overread and WiFi parsing failure or DoS. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-64515 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64515 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-2026-64515 MODERATE CHECK WITH IMPACT FROM ORIG NN MODERATE Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H';CWE-125;CWE-126;*CWE-20;Other CVSS 'AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '6.4';DESCR 'mac80211 MLE defragmentation can use a pointer to a defragmented copy while still using the original element container boundaries when reconf or EPCS MLE data is located inside a non transmitted profile. A crafted adjacent WiFi management frame can make the parser search fragments in the wrong buffer and potentially read past the intended heap object into the defragmentation scratch buffer. For the CVSS the PR:N is used because a sender in radio range does not need a local account on the target, but the attack is AV:A rather than AV:N because it requires WiFi adjacency. The realistic impact is parsing failure or limited denial of service, while the paranoid score keeps C:L/I:L/A:H because the bug is an out of bounds read in kernel heap parsing and should be manually reviewed for hidden state corruption or crash paths.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Actionable Moderate at minimum (with actual score 5) YES REMOTE KPANIC INCREASED_TO_MODERATE7_FROM_MODERATE_BASED_ON_GUESSCVSS YES NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=5 ActionableScoreLower=4 ## 1. ActionableScore * Conservative score: 4 * Paranoid score: 5 * Final recommended bucket: **Actionable Moderate at minimum**:: ## 2. Signal breakdown * Remote reachable / network-triggerable: +2. Crafted WiFi management frames can reach mac80211 parsing from an adjacent radio attacker. * Availability impact realistic: +1. The realistic outcome is parsing failure or limited DoS in the WiFi management-frame parsing path. * Broad/default/common subsystem: +1. mac80211 is a common Linux WiFi subsystem and management-frame parsing is a normal receive path. * Paranoid only, weak/indirect corruption candidate: +1. The patch context describes a possible heap overread due to mismatched element pointer and container bounds, but not an OOB write, UAF, reclaim primitive, or controlled overwrite. No strong memory corruption bonus is applied. The described overrun is read-side and likely bounded into the defragmentation scratch buffer. No confidentiality or integrity bonus is counted conservatively because no user-visible disclosure or write primitive is shown. ## 3. Reachability analysis An attacker in WiFi radio range may trigger the path by sending crafted management frames containing reconf or EPCS MLE data in a non-transmitted profile. No local account on the target is required, so the practical privilege requirement is none, but the vector is adjacent network rather than ordinary IP network. The affected path depends on WiFi MLE parsing and therefore on hardware, driver, and 802.11be or related multi-link feature exposure. Namespaces do not materially reduce the attacker requirement because the trigger is over the air. Call-site confidence: high. The patch shows the relevant parser state, stored MLE pointers, container start and length tracking, and the corrected call to cfg80211_defragment_element. ## 4. Severity interpretation This behaves more like Actionable Moderate than ordinary Moderate because it is adjacent-network reachable kernel heap parsing with a concrete OOB-read candidate. It is not a Strong Important candidate based on the provided evidence because the patch does not show UAF, OOB write, attacker-controlled overwrite, object reuse, callback control, or a demonstrated privilege-escalation path. Theoretical memory-corruption concern exists only in the paranoid sense and should be manually reviewed, but the realistic impact appears to be limited parsing failure or DoS. ## 5. One-sentence report phrase A crafted adjacent WiFi management frame can cause mac80211 MLE defragmentation to use mismatched element and container bounds, potentially leading to a bounded heap overread and WiFi parsing failure or DoS. ## 6. Manual review recommendation MANUAL CHECK REQUIRED Reason: adjacent-network reachable kernel heap parsing bugs are historically easy to under-triage, and this one has a concrete OOB-read condition even though the currently visible primitive appears constrained and not clearly exploitable for privilege escalation. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: mac80211: fix MLE defragmentation [ Upstream Commit: 1f573e17bcb7275ddd1c8f47f46ae0faf0e902a4 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1f573e17bcb7275ddd1c8f47f46ae0faf0e902a4 Changed files: net/mac80211/parse.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=1f573e17bcb7275ddd1c8f47f46ae0faf0e902a4 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-64515 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64515 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:N/A:L The Best / paranoid CVSS vector: AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H The Best / paranoid CVSS score: 6.4 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: 4 Paranoid ActionableScore: 5 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).