Vulnerability in Linux

[ Description ]Official description

In the Linux kernel, the following vulnerability has been resolved: wifi: brcmsmac: fix UAF in brcms_free_timer() brcms_free_timer() calls brcms_del_timer() which uses the non-synchronous cancel_delayed_work() to cancel the timer's underlying delayed work. If the work callback (_brcms_timer) is already running, cancel_delayed_work() returns false without waiting, and brcms_free_timer() proceeds to kfree(t) while the callback still accesses t through container_of(). Add an explicit cancel_delayed_work_sync() after brcms_del_timer() to guarantee that any in-flight callback has completed before the timer structure is freed.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund5 Oct 2026WID-SEC-2026-3743

  Linux Kernel: Multiple vulnerabilities Translated from German

  Risk mediumCVE-2026-98221CVE-2026-98181CVE-2026-98248+204 more CVEs

[ References ]References

• git.kernel.org/stable/c/050d2486e8ed2c0a23b87249ccd23e8072721391
• git.kernel.org/stable/c/10eeb0b29fd7f52487c9ae573e8d79c210a0095d
• git.kernel.org/stable/c/1edb3ddd261e973a4d577c0547e63bfa25a8170d
• git.kernel.org/stable/c/1eeca1d5e0920fbdad6449768fd2d4364e714180
• git.kernel.org/stable/c/2a4841ff0b74b495cddd31ae324e922217fc2f13
• git.kernel.org/stable/c/74acccc928851f69184271832d690607877122af
• git.kernel.org/stable/c/777cb6bba59e875b16a1d8897a483a5fecfcd5d2
• git.kernel.org/stable/c/856dabd5f2617efb23c043be9e1b22a9e6e97c41