CVE-2023-52462: 
Linux Kernel vulnerability analysis and mitigation

CVE-2023-52462 is a vulnerability in the Linux kernel's BPF (Berkeley Packet Filter) subsystem, discovered and disclosed in December 2023. The vulnerability relates to an incorrect check for attempts to corrupt spilled pointers when a register is spilled onto the stack as a 1/2/4-byte register (Kernel Patch).

The vulnerability stems from an incorrect implementation in the kernel's BPF verifier where the check for spilled registers was consulting slot_type[0] instead of slot_type[7]. When a register is spilled onto a stack as a 1/2/4-byte register, the system sets slot_type[BPF_REG_SIZE - 1] plus potentially more slots below it, depending on the actual spill size. The CVSS v3.1 base score for this vulnerability is 5.5 (Medium), with the vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N (NVD).

The vulnerability could potentially lead to corruption of spilled pointers on the stack, which could result in high integrity impact. The vulnerability requires local access and low privileges to exploit, but does not impact confidentiality or availability (NVD).

The vulnerability has been fixed in multiple Linux kernel versions. The fix involves using the is_spilled_reg() helper function instead of directly checking slot_type[0]. Patches have been released for various kernel versions including 5.10.209, 5.15.148, 6.1.75, and 6.6.14 (Kernel Patch).