CVE-2023-3640

Kernel: x86/mm: a per-cpu entry area leak was identified through the init_cea_offsets function when prefetchnta and prefetcht2 instructions being used for the per-cpu entry area mapping to the user space

Published Jul 24, 2023 CVSS 3.1 · 7 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

Vendor Workaround

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
EUVD EUVD EUVD-2023-44284 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.
History
Type Values Removed Values Added
First Time appeared Redhat rhel Els
CPEs cpe:/o:redhat:enterprise_linux:6
cpe:/o:redhat:enterprise_linux:7
cpe:/o:redhat:enterprise_linux:8
cpe:/a:redhat:enterprise_linux:8
cpe:/o:redhat:rhel_els:6
cpe:/o:redhat:rhel_els:7
Vendors & Products Redhat rhel Els
Type Values Removed Values Added
CPEs cpe:/a:redhat:enterprise_linux:9::appstream
cpe:/a:redhat:enterprise_linux:9::crb
cpe:/a:redhat:enterprise_linux:9::nfv
cpe:/a:redhat:enterprise_linux:9::realtime
cpe:/o:redhat:enterprise_linux:9::baseos
Type Values Removed Values Added
Weaknesses CWE-385
Type Values Removed Values Added
Metrics epss

{'score': 0.00136}

epss

{'score': 0.0014}

Type Values Removed Values Added
CPEs cpe:/a:redhat:enterprise_linux:9
Type Values Removed Values Added
CPEs cpe:/a:redhat:enterprise_linux:9::appstream
cpe:/a:redhat:enterprise_linux:9::crb
cpe:/a:redhat:enterprise_linux:9::nfv
cpe:/a:redhat:enterprise_linux:9::realtime
cpe:/o:redhat:enterprise_linux:9::baseos
References
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
redhat
Published
Updated
Nov 9, 2026, 3:06 AM
Reserved
Jul 12, 2023, 3:37 PM
Status
Modified
Published
Jul 24, 2023, 4:15 PM
Modified
Nov 9, 2026, 4:17 AM
Severity
Moderate
Public date
Jun 23, 2023, 12:00 AM