CVE-2023-3640

HIGHNVD 7.87.8—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.8 under NVD CVSS v3. EPSS exploit probability: 0.8%, top 49% of all CVEs by exploit prediction. GitHub Security Advisory enrichment pending alignment with NVD CVSS.

Triggered by: NVD CVSS baseline
Sources: epss, ghsa, nvd
Elevated
7.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 7.8Exploit: Elevated riskExposed: 0

A fix is available — apply it.

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.

CVSS v3
7.8
EG Score
7.8(medium)
EG Risk
51(Track)
EG Risk 51/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity78% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
53%
KEV
Not listed

Published

July 24, 2023

Last Modified

July 21, 2026

Advisory Details (3)

Auto-updated Jun 26, 2026
Patch available. Sources: redhat.
redhat Patch Available

2217523 – (CVE-2023-3640) 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

https://bugzilla.redhat.com/show_bug.cgi?id=2217523
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2023-3640
redhat Patch Available

Affected: Red Hat Enterprise Linux 9.

https://access.redhat.com/errata/RHSA-2023:6583

Vendor Advisories for CVE-2023-3640(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatkernel-0:5.14.0-362.8.1.el9_32023-11-07redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
linux5.10.103-1 ... 7.2~rc5-1~exp1 (499 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 7.2~rc5-1~exp1 (337 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.2~rc5-1~exp1 (161 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.2~rc5-1~exp1 (161 versions)——

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 8× in last 7d / 31× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 167 total refreshes for this CVE.

  1. 2026-09-07 15:59 UTCEPSS rescore
  2. 2026-09-06 13:45 UTCEPSS rescore
  3. 2026-09-06 13:45 UTCEPSS rescore
  4. 2026-09-05 15:26 UTCEPSS rescore
  5. 2026-09-04 13:58 UTCEPSS rescore
  6. 2026-09-04 05:04 UTCEPSS rescore
  7. 2026-09-03 22:59 UTCOSV refresh
  8. 2026-09-02 14:09 UTCEPSS rescore
  9. 2026-09-01 13:51 UTCEPSS rescore
  10. 2026-08-30 19:15 UTCEPSS rescore
  11. 2026-08-30 01:20 UTCEPSS rescore
  12. 2026-08-28 21:39 UTCEPSS rescore
  13. 2026-08-27 14:23 UTCEPSS rescore
  14. 2026-08-26 14:44 UTCEPSS rescore
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  16. 2026-08-25 13:46 UTCEPSS rescore
  17. 2026-08-23 00:17 UTCEPSS rescore
  18. 2026-08-21 23:47 UTCEPSS rescore
  19. 2026-08-20 22:53 UTCEPSS rescore
  20. 2026-08-19 17:02 UTCEPSS rescore
  21. 2026-08-19 17:02 UTCEPSS rescore
  22. 2026-08-18 13:46 UTCEPSS rescore
  23. 2026-08-17 13:45 UTCEPSS rescore
  24. 2026-08-17 12:16 UTCOSV refresh
  25. 2026-08-16 14:54 UTCEPSS rescore
Show 75 more
  1. 2026-08-16 02:12 UTCEPSS rescore
  2. 2026-08-15 01:28 UTCEPSS rescore
  3. 2026-08-15 01:28 UTCEPSS rescore
  4. 2026-08-13 21:58 UTCEPSS rescore
  5. 2026-08-12 13:48 UTCEPSS rescore
  6. 2026-08-11 13:39 UTCEPSS rescore
  7. 2026-08-09 13:44 UTCEPSS rescore
  8. 2026-08-09 13:44 UTCEPSS rescore
  9. 2026-08-08 16:35 UTCEPSS rescore
  10. 2026-08-07 16:25 UTCEPSS rescore
  11. 2026-08-06 13:45 UTCEPSS rescore
  12. 2026-08-05 19:15 UTCEPSS rescore
  13. 2026-08-04 15:07 UTCEPSS rescore
  14. 2026-08-03 10:34 UTCEPSS rescore
  15. 2026-08-03 10:34 UTCEPSS rescore
  16. 2026-08-02 06:45 UTCOSV refresh
  17. 2026-08-02 02:25 UTCEPSS rescore
  18. 2026-08-02 02:25 UTCEPSS rescore
  19. 2026-08-01 04:14 UTCEPSS rescore
  20. 2026-08-01 04:13 UTCEPSS rescore
  21. 2026-07-30 16:26 UTCEPSS rescore
  22. 2026-07-30 16:26 UTCEPSS rescore
  23. 2026-07-30 01:28 UTCEPSS rescore
  24. 2026-07-30 01:28 UTCEPSS rescore
  25. 2026-07-28 15:34 UTCEPSS rescore
  26. 2026-07-28 15:34 UTCEPSS rescore
  27. 2026-07-26 14:52 UTCEPSS rescore
  28. 2026-07-26 14:52 UTCEPSS rescore
  29. 2026-07-25 14:16 UTCEPSS rescore
  30. 2026-07-24 14:16 UTCEPSS rescore
  31. 2026-07-23 14:16 UTCEPSS rescore
  32. 2026-07-23 14:16 UTCEPSS rescore
  33. 2026-07-23 02:24 UTCEG score recompute
  34. 2026-07-22 23:11 UTCEG score recompute▲ 0.80
  35. 2026-07-22 14:06 UTCEPSS rescore
  36. 2026-07-21 15:23 UTCEPSS rescore
  37. 2026-07-21 15:23 UTCEPSS rescore
  38. 2026-07-20 17:06 UTCEPSS rescore
  39. 2026-07-19 14:29 UTCEPSS rescore
  40. 2026-07-19 02:27 UTCEPSS rescore
  41. 2026-07-18 10:03 UTCEPSS rescore
  42. 2026-07-18 10:03 UTCEPSS rescore
  43. 2026-07-16 17:01 UTCEPSS rescore
  44. 2026-07-16 17:01 UTCEPSS rescore
  45. 2026-07-15 16:56 UTCEPSS rescore
  46. 2026-07-15 16:56 UTCEPSS rescore
  47. 2026-07-15 14:19 UTCOSV refresh
  48. 2026-07-15 01:58 UTCEPSS rescore
  49. 2026-07-13 22:28 UTCEPSS rescore
  50. 2026-07-13 22:28 UTCEPSS rescore
  51. 2026-07-13 06:11 UTCEPSS rescore
  52. 2026-07-13 06:11 UTCEPSS rescore
  53. 2026-07-12 05:45 UTCEPSS rescore
  54. 2026-07-12 05:45 UTCEPSS rescore
  55. 2026-07-11 08:26 UTCEPSS rescore
  56. 2026-07-11 08:26 UTCEPSS rescore
  57. 2026-07-09 19:08 UTCEPSS rescore
  58. 2026-07-08 15:13 UTCEPSS rescore
  59. 2026-07-07 13:44 UTCEPSS rescore
  60. 2026-07-06 16:26 UTCEPSS rescore
  61. 2026-07-06 16:26 UTCEPSS rescore
  62. 2026-07-06 02:22 UTCEPSS rescore
  63. 2026-07-05 02:29 UTCEPSS rescore
  64. 2026-07-04 06:29 UTCEPSS rescore
  65. 2026-07-01 15:05 UTCEPSS rescore
  66. 2026-06-30 23:21 UTCEPSS rescore
  67. 2026-06-30 23:21 UTCEPSS rescore
  68. 2026-06-28 14:06 UTCEPSS rescore
  69. 2026-06-28 14:06 UTCEPSS rescore
  70. 2026-06-28 04:55 UTCEPSS rescore
  71. 2026-06-28 04:55 UTCEPSS rescore
  72. 2026-06-27 14:34 UTCOSV refresh
  73. 2026-06-27 03:07 UTCEPSS rescore
  74. 2026-06-27 03:07 UTCEPSS rescore
  75. 2026-06-26 11:39 UTCNVD updateCVSS v3 → 7.8

Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCpray77/CVE-2023-3640
    First seen Jun 20, 2023

    SCTF 2023 kernel pwn && CVE-2023-3640

    Open source ↗

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2023-3640?
CVE-2023-3640 is a high vulnerability published on July 24, 2023. A possible unauthorized memory access flaw was found in the Linux kernel's cpuentryarea 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…
When was CVE-2023-3640 disclosed?
CVE-2023-3640 was first published in the National Vulnerability Database on July 24, 2023, with the most recent update on July 21, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2023-3640 actively exploited?
CVE-2023-3640 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 47.0% of all scored CVEs.
What is the CVSS score of CVE-2023-3640?
CVE-2023-3640 has a CVSS v3 base score of 7.8 (NVD).
How do I remediate CVE-2023-3640?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2023-3640, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2023-3640

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