CVE-2024-35811: Debian Linux

Medium severity, CVSS 5.5. EPSS: 0.4% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: Fix use-after-free bug in brcmf_cfg80211_detach This is the candidate patch of CVE-2023-47233 : https://nvd.nist.gov/vuln/detail/CVE-2023-47233 In brcm80211 driver,it starts with the following invoking chain to start init a timeout worker: ->brcmf_usb_probe ->brcmf_usb_probe_cb ->brcmf_attach ->brcmf_bus_started ->brcmf_cfg80211_attach ->wl_init_priv ->brcmf_init_escan ->INIT_WORK(&cfg->escan_timeout_work, brcmf_cfg80211_escan_timeout_worker); If we disconnect the USB by hotplug, it will call brcmf_usb_disconnect to make cleanup. The invoking chain is : brcmf_usb_disconnect ->brcmf_usb_disconnect_cb ->brcmf_detach ->brcmf_cfg80211_detach ->kfree(cfg); While the timeout woker may still be running. This will cause a use-after-free bug on cfg in brcmf_cfg80211_escan_timeout_worker. Fix it by deleting the timer and canceling the worker in brcmf_cfg80211_detach. [arend.vanspriel@broadcom.com: keep timer delete as is and cancel work just before free]

Affected products

• Debian Debian Linux: version 10.0 only
• Linux Linux Kernel: from 3.7, before 4.19.312 (fixed in 4.19.312); from 4.20, before 5.4.274 (fixed in 5.4.274); from 5.5, before 5.10.215 (fixed in 5.10.215); from 5.11, before 5.15.154 (fixed in 5.15.154); from 5.16, before 6.1.84 (fixed in 6.1.84); from 6.2, before 6.6.24 (fixed in 6.6.24); …

Published 2024-05-17. Last modified 2026-08-04.