Bug 2502295 (CVE-2026-63869) - CVE-2026-63869 kernel: wifi: mac80211: limit injected antenna index in ieee80211_parse_tx_radiotap
Summary: CVE-2026-63869 kernel: wifi: mac80211: limit injected antenna index in ieee80...
Keywords:
Status: NEW
Alias: CVE-2026-63869
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-07-19 15:02 UTC by OSIDB Bzimport
Modified: 2026-09-17 12:15 UTC (History)
2 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:


Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2026:68507 0 None None None 2026-09-17 05:45:12 UTC
Red Hat Product Errata RHSA-2026:68570 0 None None None 2026-09-17 12:15:56 UTC

Description OSIDB Bzimport 2026-07-19 15:02:28 UTC
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.

Comment 6 Jon Orris 2026-09-17 05:45:12 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:68507 https://access.redhat.com/errata/RHSA-2026:68507

Comment 7 Jon Orris 2026-09-17 12:15:55 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:68570 https://access.redhat.com/errata/RHSA-2026:68570


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