CVE-2023-6546

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A race condition was found in the GSM 0710 tty multiplexor in the Linux kernel. This issue occurs when two threads execute the GSMIOC SETCONF ioctl on the same tty file descriptor with the gsm line discipline enabled, and can lead to a use-after-free problem on a struct gsm dlci while restarting the gsm mux. This could allow a local unprivileged user to escalate their privileges on the system. The exploit bypasses KASLR by leaking the kernel address from world-readable /sys/kernel/notes. To bypass SMAP, the author used a novel technique of filling the kernfs pr cont buf global variable with controlled data from userspace.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.