CVE-2025-71127 — wifi: mac80211: Discard Beacon frames to non-broadcast address
In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: Discard Beacon frames to non-broadcast address Beacon frames are required to be sent to the broadcast address, see IEEE Std 802.11-2020, 11.1.3.1 ("The Address 1 field of the Beacon .. frame shall be set to the broadcast address"). A unicast Beacon frame might be used as a targeted attack to get one of the associated STAs to do something (e.g., using CSA to move it to another channel). As such, it is better have strict filtering for this on the received side and discard all Beacon frames that are sent to an unexpected address. This is even more important for cases where beacon protection is used. The current implementation in mac80211 is correctly discarding unicast Beacon frames if the Protected Frame bit in the Frame Control field is set to 0. However, if that bit is set to 1, the logic used for checking for configured BIGTK(s) does not actually work. If the driver does not have logic for dropping unicast Beacon frames with Protected Frame bit 1, these frames would be accepted in mac80211 processing as valid Beacon frames even though they are not protected. This would allow beacon protection to be bypassed. While the logic for checking beacon protection could be extended to cover this corner case, a more generic check for discard all Beacon frames based on A1=unicast address covers this without needing additional changes. Address all these issues by dropping received Beacon frames if they are sent to a non-broadcast address.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+2
- Technical severity (medium)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux, Linux Linux Kernel).
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux | version 5.7≥ af2d14b01c32d7cba65f73503586e5b621afb139 and < 193d18f60588e95d62e0f82b6a53893e5f2f19f8≥ af2d14b01c32d7cba65f73503586e5b621afb139 and < a21704df4024708be698fb3fd5830d5b113b70e0≥ af2d14b01c32d7cba65f73503586e5b621afb139 and < 7b240a8935d554ad36a52c2c37c32039f9afaef2≥ af2d14b01c32d7cba65f73503586e5b621afb139 and < 6e5bff40bb38741e40c33043ba0816fba5f93661≥ af2d14b01c32d7cba65f73503586e5b621afb139 and < 88aab153d1528bc559292a12fb5105ee97528e1f≥ af2d14b01c32d7cba65f73503586e5b621afb139 and < 0a59a3895f804469276d188effa511c72e752f35≥ af2d14b01c32d7cba65f73503586e5b621afb139 and < be0974be5c42584e027883ac2af7dab5e950098c | Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
version 6.19-rc5version 6.19-rc8version 6.19-rc7version 6.19-rc6≥ 5.7.1 and < 5.10.248version 6.19-rc4version 6.19-rc3version 6.19-rc2 and 7 moreversion 6.19-rc1version 5.7≥ 6.13 and < 6.18.4≥ 6.7 and < 6.12.65≥ 6.2 and < 6.6.120≥ 5.16 and < 6.1.160≥ 5.11 and < 5.15.198 |
Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.1 | CVSS 3.1 | High | 2.8 | 4.2 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.1 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
| 5.5 | CVSS 3.1 | Medium | 1.8 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov) EPSS over time FIRST
Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 0.23%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- SSVC assessment updated
- Record published
- Fix documented
- CVSS changed · 5.5
- Source status changed · → Modified
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
7 on the record
- git.kernel.org/stable/c/0a59a3895f804469276d188effa511c72e752f35
- git.kernel.org/stable/c/be0974be5c42584e027883ac2af7dab5e950098c
- git.kernel.org/stable/c/a21704df4024708be698fb3fd5830d5b113b70e0
- git.kernel.org/stable/c/193d18f60588e95d62e0f82b6a53893e5f2f19f8
- git.kernel.org/stable/c/88aab153d1528bc559292a12fb5105ee97528e1f
- git.kernel.org/stable/c/7b240a8935d554ad36a52c2c37c32039f9afaef2
- git.kernel.org/stable/c/6e5bff40bb38741e40c33043ba0816fba5f93661
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 22h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 22h
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
- Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2025-71127 is "wifi: mac80211: Discard Beacon frames to non-broadcast address", rated Medium. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.23% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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