CVE-2023-3640: Linux Kernel

High severity, CVSS 7.8. EPSS: 0.8% chance of exploitation in the next 30 days.

A possible unauthorized memory access flaw was found in the Linux kernel's cpu_entry_area mapping of X86 CPU data to memory, where a user may guess the location of exception stacks or other important data. Based on the previous CVE-2023-0597, the 'Randomize per-cpu entry area' feature was implemented in /arch/x86/mm/cpu_entry_area.c, which works through the init_cea_offsets() function when KASLR is enabled. However, despite this feature, there is still a risk of per-cpu entry area leaks. This issue could allow a local user to gain access to some important data with memory in an expected location and potentially escalate their privileges on the system.

Affected products

• Linux Linux Kernel: affected versions not specified
• Red Hat Enterprise Linux: version 8.0 only; version 9.0 only

Published 2023-07-24. Last modified 2026-07-21.