CVE-2026-68304 wifi: brcmfmac: fix 802.1X-SHA256 call trace warning
A local attacker can trigger a kernel warning and potential denial of service in the brcmfmac Wi-Fi driver by configuring 802.1X-SHA256 authentication.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-68304?
CVE-2026-68304 is a denial of service vulnerability in Linux, published on 10 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: fix 802.1X-SHA256 call trace warning
Based on wpa_auth as 1x_256 mode, need to set up "use_fwsup" with BRCMF_PROFILE_FWSUP_1X. Or it will happen trace warning when call brcmf_cfg80211_set_pmk().
[ 4481.831101] ------------[ cut here ]------------ [ 4481.831102] WARNING: CPU: 1 PID: 2997 at drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c:7242 brcmf_cfg80211_set_pmk+0x77/0xd0 [brcmfmac] [...] [ 4481.831202] Call Trace: [ 4481.831204] <TASK> [ 4481.831205] nl80211_set_pmk+0x183/0x250 [cfg80211] [ 4481.831233] genl_family_rcv_msg_doit+0xea/0x150 [ 4481.831237] genl_rcv_msg+0x104/0x240 [ 4481.831239] ? cfg80211_probe_status+0x2c0/0x2c0 [cfg80211] [ 4481.831257] ? genl_family_rcv_msg_doit+0x150/0x150 [ 4481.831259] netlink_rcv_skb+0x4e/0x100 [ 4481.831261] genl_rcv+0x24/0x40 [ 4481.831262] netlink_unicast+0x236/0x380 [ 4481.831264] netlink_sendmsg+0x250/0x4b0 [ 4481.831266] sock_sendmsg+0x5c/0x70 [ 4481.831269] ____sys_sendmsg+0x236/0x2b0 [ 4481.831271] ? copy_msghdr_from_user+0x6d/0xa0 [ 4481.831272] ___sys_sendmsg+0x86/0xd0 [ 4481.831274] ? avc_has_perm+0x8c/0x1a0 [ 4481.831276] ? preempt_count_add+0x6a/0xa0 [ 4481.831279] ? sock_has_perm+0x82/0xa0 [ 4481.831280] __sys_sendmsg+0x57/0xa0 [ 4481.831282] do_syscall_64+0x38/0x90 [ 4481.831284] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 4481.831286] RIP: 0033:0x7fd270d369b4
Which versions are affected by CVE-2026-68304?
How do I fix CVE-2026-68304?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-68304 being exploited?
There is no known exploitation of CVE-2026-68304 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-68304, DEBIAN-CVE-2026-68304, GHSA-gqh4-q6g4-cvr4, UBUNTU-CVE-2026-68304.