{"id":"CVE-2023-3640","title":"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","summary":"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-…","severity":"high","cvss":7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-385","CWE-203"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel","enterprise_linux = 8.0","enterprise_linux = 9.0"],"published":"2023-07-24","updated":"2026-06-26","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2023-3640","references":[{"url":"https://access.redhat.com/errata/RHSA-2023:6583","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/security/cve/CVE-2023-3640","label":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2217523","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/security/cve/CVE-2023-3640","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2217523","label":"af854a3a-2127-422b-91ae-364da2661108"}],"tags":["nvd","exploit-available"],"epss":0.00761,"epssPercentile":0.53365,"ingestedAt":"2026-06-26T16:43:13.373Z","exploits":{"github":1,"githubRepos":["https://github.com/pray77/CVE-2023-3640"],"checkedAt":"2026-09-21T15:25:51.348Z"},"exploitAvailable":true,"slug":"CVE-2023-3640","body":"## Overview\n\nA 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.\n\n## Affected\n\n- `linux_kernel`\n- `enterprise_linux = 8.0`\n- `enterprise_linux = 9.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":51,"depthScoreParts":{"impact":38.5,"likelihood":0.2,"exploitation":12,"ransomware":0},"changes":[{"seq":4653,"id":"CVE-2023-3640","ts":1788887197302,"field":"exploit_available","old":"false","new":"true"},{"seq":3536,"id":"CVE-2023-3640","ts":1788886313386,"field":"exploit_available","old":"true","new":"false"},{"seq":2390,"id":"CVE-2023-3640","ts":1788882982694,"field":"exploit_available","old":"false","new":"true"},{"seq":1419,"id":"CVE-2023-3640","ts":1788882395585,"field":"exploit_available","old":"true","new":"false"},{"seq":533,"id":"CVE-2023-3640","ts":1788881831712,"field":"exploit_available","old":"false","new":"true"}]}