VulnerabilityAwaiting classification

CVE-2026-64515

HIGH · 8.3 CVSS v3.1 Published 2026-07-25
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
88/100
Remediation priority · High
No privileges Zero-click 4 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: fix MLE defragmentation If either reconf or EPCS multi-link element (MLE) is contained in a non-transmitted profile, the defragmentation routine is called with a pointer to the defragmented copy, but the original elements. This is incorrect for two reasons: - if the original defragmentation was needed, it will not find the correct data - if the original frame is at a higher address, the parsing will potentially overrun the heap data (though given the layout of the buffers, only into the new defragmentation buffer, and then it has to stop and fail once that's filled with copied data. Fix it by tracking the container along with the pointer and in doing so also unify the two almost identical defragmentation routines.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A memory safety vulnerability in Linux kernel's mac80211 wifi driver where the MLE (Multi-Link Element) defragmentation routine uses mismatched pointers - a pointer to the defragmented copy but with original element data. This can cause incorrect defragmentation results or potential heap buffer overrun when parsing frames at higher addresses.

MitigationApply the Linux kernel patch that corrects the defragmentation routine to properly track the container along with the pointer, ensuring the defragmented data and elements are correctly associated.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
Low
Availability
High

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check kernel version for patch status
    Run 'uname -r' to get the running kernel version. Check if the fix commit (unifying MLE defragmentation routines with proper container tracking) has been applied by comparing against recent kernel releases or consulting kernel security advisories.
    Affected if The kernel version is older than the version containing the mac80211 MLE defragmentation fix.
  2. Verify mac80211 wireless driver is in use
    Run 'lsmod | grep mac80211' or check 'iw list' to see if the mac80211 driver stack is loaded and active on the system.
    Affected if The mac80211 driver module is loaded and manages wireless interfaces.
  3. Check for active WiFi interfaces
    Run 'ip link show' or 'iw dev' to list wireless interfaces in the UP state. Also check 'rfkill list wifi' to see if WiFi is unblocked.
    Affected if A WiFi interface exists and is enabled (not hard-blocked or soft-blocked).
  4. Inspect multi-link element capability
    Run 'iw dev <interface> link' or check 'iw list' output for Multi-Link (MLD) capabilities and active multi-link configurations.
    Affected if The wireless device supports and has multi-link operations enabled, which triggers the vulnerable MLE defragmentation code path.

The system is affected if running an unpatched kernel with mac80211 WiFi active and multi-link operations enabled, exposing the reception-path to potential heap overflow from the pointer-element mismatch.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the Linux kernel patch that corrects the defragmentation routine to properly track the container along with the pointer, ensuring the defragmented data and elements are correctly associated.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing12.0 h
  • Review / QA4.0 h
28.0 hours of engineering $4,760
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-64515 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
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  • Version or environment caveats, and links to real fixes
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