Junglewise Threat Intelligence

CVE-2024-43879: Linux Kernel denial of service in cfg80211 Wi-Fi bitrate calculation

CVE-2024-43879 · Severity: medium · CVSS 5.5 · Published 2024-08-21

Technologies: Linux Kernel. Vendors: Linux.

Executive brief

A vulnerability in the Linux kernel's wireless networking component could allow a local user to trigger a system warning or potential instability. The issue occurs when the system processes specific high-speed Wi-Fi (HE) data rates that it does not correctly recognize. While primarily a stability concern, it could be used to disrupt wireless operations on affected devices.

Technical details

A vulnerability exists in the cfg80211_calculate_bitrate_he() function within net/wireless/util.c of the Linux kernel. The component fails to handle the NL80211_RATE_INFO_HE_RU_ALLOC_2x996 allocation type, which triggers a WARN_ON_ONCE macro when encountered. A local attacker with sufficient privileges to influence wireless rate information could potentially trigger this code path, leading to kernel log flooding or system instability (Denial of Service). The fix involves explicitly handling the 2x996 RU allocation similarly to 160 MHz bandwidth calculations. Patches have been released across multiple stable kernel branches.

Affected products

  • Linux Linux Kernel 4.19 to 4.19.320, 4.20 to 5.4.282, 5.5 to 5.10.224, 5.11 to 5.15.165, 5.16 to 6.1.103, 6.2 to 6.6.44, 6.7 to 6.10.3

Timeline

  • 2024-08-03: patched: Fix committed to various stable kernel trees.
  • 2024-08-21: disclosed: CVE-2024-43879 published.

References

Related threats