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Fencer Intel
high 7.6

CVE-2026-63869 json

wifi: mac80211: limit injected antenna index in ieee80211_parse_tx_radiotap

published 3mo ago modified 16d ago also EUVD-2026-45554

cvss
7.6
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 17%
public exploits
0
none known

Summary

In the Linux kernel, the following vulnerability has been resolved:

wifi: mac80211: limit injected antenna index in ieee80211_parse_tx_radiotap

When parsing the radiotap header of an injected frame, ieee80211_parse_tx_radiotap() uses the IEEE80211_RADIOTAP_ANTENNA value directly as a shift count:

info->control.antennas |= BIT(*iterator.this_arg);

*iterator.this_arg is an 8-bit value taken straight from the frame supplied by userspace, so BIT() can be asked to shift by up to 255. That is undefined behaviour on the unsigned long and is reported by UBSAN:

UBSAN: shift-out-of-bounds in net/mac80211/tx.c:2174:30 shift exponent 235 is too large for 64-bit type 'unsigned long' Call Trace: ieee80211_parse_tx_radiotap+0xadb/0x1950 net/mac80211/tx.c:2174 ieee80211_monitor_start_xmit+0xb1f/0x1250 net/mac80211/tx.c:2451 ... packet_sendmsg+0x3eb6/0x50f0 net/packet/af_packet.c:3109

info->control.antennas is a 2-bit bitmap (u8 antennas:2), so only antenna indices 0 and 1 can ever be represented. Ignore any larger value instead of shifting out of bounds.

Patch / fix

  • Linux Linux 6.12.94, 6.18.36, 7.0.13, 7.1
  • linux Debian 13 6.12.94-1
  • linux Debian 14 7.0.13-1

debian advisories DEBIAN-CVE-2026-63869

  • linux Ubuntu 24.04 LTS 6.8.0-146.146
  • linux Ubuntu 26.04 LTS 7.0.0-31.31
  • linux-aws Ubuntu 24.04 LTS 6.8.0-1066.69
  • linux-aws Ubuntu 26.04 LTS 7.0.0-1012.12
  • linux-gcp Ubuntu 24.04 LTS 6.8.0-1070.78
  • linux-gcp Ubuntu 26.04 LTS 7.0.0-1011.11
  • linux-gke Ubuntu 24.04 LTS 6.8.0-1065.73
  • linux-gke Ubuntu 26.04 LTS 7.0.0-1006.7

ubuntu advisories UBUNTU-CVE-2026-63869

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel RHEL 9 5.14.0-687.49.1.el9_8
  • rv RHEL 9 5.14.0-687.49.1.el9_8
  • perf RHEL 9 5.14.0-687.49.1.el9_8
  • rtla RHEL 9 5.14.0-687.49.1.el9_8
  • libperf RHEL 9 5.14.0-687.49.1.el9_8
  • kernel-rt RHEL 9 5.14.0-687.49.1.el9_8
  • kernel-64k RHEL 9 5.14.0-687.49.1.el9_8
  • kernel-core RHEL 9 5.14.0-687.49.1.el9_8

red hat advisories RHSA-2026:68570RHSA-2026:68507

  • kernel-rt Real Time Module 15 SP7 6.4.0-150700.7.72.1
  • kernel-syms-rt Real Time Module 15 SP7 6.4.0-150700.7.72.1
  • kernel-source-rt Real Time Module 15 SP7 6.4.0-150700.7.72.1
  • kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.78.1
  • kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.78.1
  • kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.78.1
  • kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.78.1
  • kernel-default SLE Workstation Extension 15 SP7, SLE Module for Legacy 15 SP7, SLE Module for Basesystem 15 SP7 +2 more 6.4.0-150700.53.78.1

suse advisories SUSE-SU-2026:3810-1SUSE-SU-2026:3790-1SUSE-SU-2026:23244-1SUSE-SU-2026:23241-1SUSE-SU-2026:23194-1SUSE-SU-2026:23193-1

  • kernel-rt openSUSE Leap 16.0 6.12.0-160000.37.1
  • dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.37.1
  • kernel-64kb openSUSE Leap 16.0 6.12.0-160000.37.1
  • kernel-syms openSUSE Leap 16.0 6.12.0-160000.37.1
  • kernel-azure openSUSE Leap 16.0 6.12.0-160000.37.1
  • kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.37.1
  • kernel-source openSUSE Leap 16.0 6.12.0-160000.37.1
  • kernel-default openSUSE Leap 16.0 6.12.0-160000.37.1

opensuse advisories openSUSE-SU-2026:21555-1

  • kernel AlmaLinux 10 6.12.0-211.56.1.el10_2
  • rv AlmaLinux 10 6.12.0-211.56.1.el10_2
  • perf AlmaLinux 10 6.12.0-211.56.1.el10_2
  • rtla AlmaLinux 10 6.12.0-211.56.1.el10_2
  • libperf AlmaLinux 10 6.12.0-211.56.1.el10_2
  • kernel-rt AlmaLinux 10 6.12.0-211.56.1.el10_2
  • kernel-64k AlmaLinux 10 6.12.0-211.56.1.el10_2
  • kernel-core AlmaLinux 10 6.12.0-211.56.1.el10_2

almalinux advisories ALSA-2026:68507ALSA-2026:68570

  • kernel Rocky Linux 10 6.12.0-211.56.1.el10_2.0.1
  • kernel Rocky Linux 9 5.14.0-687.49.1.el9_8

rocky linux advisories RLSA-2026:68507RLSA-2026:68570

Is CVE-2026-63869 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-63869 updated cvss 7.6

kernel: wifi: mac80211: limit injected antenna index in ieee80211_parse_tx_radiotap

  • Red Hat Enterprise Linux AppStream (v. 9) rv 5.14.0-687.49.1.el9_8, perf 5.14.0-687.49.1.el9_8, rtla 5.14.0-687.49.1.el9_8, python3-perf 5.14.0-687.49.1.el9_8, kernel-devel-matched 5.14.0-687.49.1.el9_8, kernel-64k-devel-matched 5.14.0-687.49.1.el9_8, +7 more
    fixed: vendor fix RHSA-2026:68570
  • Red Hat Enterprise Linux AppStream (v. 10) rv 6.12.0-211.56.1.el10_2, perf 6.12.0-211.56.1.el10_2, rtla 6.12.0-211.56.1.el10_2, python3-perf 6.12.0-211.56.1.el10_2, kernel-devel-matched 6.12.0-211.56.1.el10_2, kernel-64k-devel-matched 6.12.0-211.56.1.el10_2, +7 more
    fixed: vendor fix RHSA-2026:68507
  • Red Hat Enterprise Linux BaseOS (v. 9) kernel 5.14.0-687.49.1.el9_8, kernel-64k 5.14.0-687.49.1.el9_8, kernel-core 5.14.0-687.49.1.el9_8, kernel-tools 5.14.0-687.49.1.el9_8, kernel-modules 5.14.0-687.49.1.el9_8, kernel-64k-core 5.14.0-687.49.1.el9_8, +27 more
    fixed: vendor fix RHSA-2026:68570
  • Red Hat Enterprise Linux BaseOS (v. 10) kernel 6.12.0-211.56.1.el10_2, kernel-64k 6.12.0-211.56.1.el10_2, kernel-core 6.12.0-211.56.1.el10_2, kernel-tools 6.12.0-211.56.1.el10_2, kernel-modules 6.12.0-211.56.1.el10_2, kernel-64k-core 6.12.0-211.56.1.el10_2, +28 more
    fixed: vendor fix RHSA-2026:68507
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) libperf 5.14.0-687.49.1.el9_8, kernel-debuginfo-common-s390x 5.14.0-687.49.1.el9_8, kernel-debuginfo-common-x86_64 5.14.0-687.49.1.el9_8, kernel-debuginfo-common-aarch64 5.14.0-687.49.1.el9_8, kernel-debuginfo-common-ppc64le 5.14.0-687.49.1.el9_8
    fixed: vendor fix RHSA-2026:68570
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) libperf 6.12.0-211.56.1.el10_2, kernel-debuginfo-common-s390x 6.12.0-211.56.1.el10_2, kernel-debuginfo-common-x86_64 6.12.0-211.56.1.el10_2, kernel-debuginfo-common-aarch64 6.12.0-211.56.1.el10_2, kernel-debuginfo-common-ppc64le 6.12.0-211.56.1.el10_2
    fixed: vendor fix RHSA-2026:68507
  • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt 5.14.0-687.49.1.el9_8, kernel-rt-64k 5.14.0-687.49.1.el9_8, kernel-rt-core 5.14.0-687.49.1.el9_8, kernel-rt-modules 5.14.0-687.49.1.el9_8, kernel-rt-64k-core 5.14.0-687.49.1.el9_8, kernel-rt-debug-core 5.14.0-687.49.1.el9_8, +14 more
    fixed: vendor fix RHSA-2026:68570
  • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt 6.12.0-211.56.1.el10_2, kernel-rt-64k 6.12.0-211.56.1.el10_2, kernel-rt-core 6.12.0-211.56.1.el10_2, kernel-rt-modules 6.12.0-211.56.1.el10_2, kernel-rt-64k-core 6.12.0-211.56.1.el10_2, kernel-rt-debug-core 6.12.0-211.56.1.el10_2, +14 more
    fixed: vendor fix RHSA-2026:68507
show 3 more
  • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt 5.14.0-687.49.1.el9_8, kernel-rt-core 5.14.0-687.49.1.el9_8, kernel-rt-modules 5.14.0-687.49.1.el9_8, kernel-rt-debug-core 5.14.0-687.49.1.el9_8, kernel-rt-modules-core 5.14.0-687.49.1.el9_8, kernel-rt-debug-modules 5.14.0-687.49.1.el9_8, +4 more
    fixed: vendor fix RHSA-2026:68570
  • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt 6.12.0-211.56.1.el10_2, kernel-rt-core 6.12.0-211.56.1.el10_2, kernel-rt-modules 6.12.0-211.56.1.el10_2, kernel-rt-debug-core 6.12.0-211.56.1.el10_2, kernel-rt-modules-core 6.12.0-211.56.1.el10_2, kernel-rt-debug-modules 6.12.0-211.56.1.el10_2, +4 more
    fixed: vendor fix RHSA-2026:68507
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 kernel-rt, kernel-rt-kvm, kernel-rt-core, kernel-rt-modules, kernel-rt-debug-kvm, kernel-rt-debug-core, +12 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
26d ago

Exploit prediction

0.26% chance of exploitation in the next 30 days, higher than 17% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 7.6 CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L

Affected products

  • Linux Linux

Classification

Weakness
  • CWE-190 Integer Overflow or Wraparound
  • CWE-1284 Improper Validation of Specified Quantity in Input
Technology feeds

References

Sources

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