A double free vulnerability was found in the vmwgfx driver in the Linux kernel. Quoting ZDI security advisory [1]: "This vulnerability allows local attackers to escalate privileges on affected installations of Linux Kernel. An attacker must first obtain the ability to execute high-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the handling of vmw_buffer_object objects. The issue results from the lack of validating the existence of an object prior to performing further free operations on the object. An attacker can leverage this vulnerability to escalate privileges and execute code in the context of the kernel." [1] https://www.zerodayinitiative.com/advisories/ZDI-CAN-20292/
Upstream fix: https://github.com/torvalds/linux/commit/9ef8d83 Note that the same commit fixed both this issue and CVE-2023-33951 (bug 2218195).