CVE-2021-21551

CRITICALNVD 8.89.0▲
EchelonGraph scoreHIGH confidence

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2022-03-31), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 8.8 retained for reference. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, epss, ghsa, nvd
Trending — 4 sources updated this weekExploited in the wild
9.0EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS PROB: 79%CVSS: 8.8Exploit: cisa kev · ssvc active · Metasploit · epss top5pct · epss high · public exploitExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Dell dbutil_2_3.sys driver contains an insufficient access control vulnerability which may lead to escalation of privileges, denial of service, or information disclosure. Local authenticated user access is required.

CVSS v3
8.8
EG Score
9.0(high)
EG Risk
81(Attend)
EG Risk 81/100SSVC: Attend

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
Severity90% × 45%
Exploitation100% × 40%
Automatability0% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
79%
EPSS %ILE
100%
KEV
⚠ Exploited

Published

May 4, 2021

Last Modified

October 28, 2025

Advisory Details (2)

Auto-updated Jun 2, 2026
⚠️ Active exploitation confirmed. Patch available. Sources: cisa.
cisa Patch Available🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21551
generic

DSA-2021-088: Dell Client Platform Security Update for an Insufficient Access Control Vulnerability in the Dell dbutil Driver | Dell US

https://www.dell.com/support/kbdoc/en-us/000186019/dsa-2021-088-dell-client-platform-security-update-for-dell-driver-insufficient-access-control-vulnerability

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 55× in last 7d / 228× 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 829 total refreshes for this CVE.

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

Publicly available exploits

(10 references)

Working exploit code is in the public domain (1 Metasploit module) (8 GitHub PoCs) (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCEap2468/CVE-2021-21551
    First seen Aug 2, 2024

    Proof of concept exploit for CVE-2021-21551

    Open source ↗
  • GitHub PoCnanabingies/CVE-2021-21551
    First seen Jan 7, 2023

    Dell Driver EoP (CVE-2021-21551)

    Open source ↗
  • GitHub PoCtijme/kernel-mii
    First seen Jun 25, 2022

    Cobalt Strike (CS) Beacon Object File (BOF) foundation for kernel exploitation using CVE-2021-21551.

    Open source ↗
  • GitHub PoCihack4falafel/Dell-Driver-EoP-CVE-2021-21551
    First seen Sep 3, 2021

    Dell Driver EoP (CVE-2021-21551)

    Open source ↗
  • GitHub PoCmzakocs/CVE-2021-21551-POC
    First seen Jun 2, 2021

    An extended proof-of-concept for the CVE-2021-21551 Dell ‘dbutil_2_3.sys’ Kernel Exploit

    Open source ↗
  • GitHub PoCmathisvickie/CVE-2021-21551
    First seen May 30, 2021

    arbitrary kernel read/write in dbutil_2_3.sys, Proof of Concept Local Privilege Escalation to nt authority/system

    Open source ↗
  • Exploit-DBEDB-49893
    First seen May 21, 2021

    DELL dbutil_2_3.sys 2.3 - Arbitrary Write to Local Privilege Escalation (LPE)

    Open source ↗
  • GitHub PoCch3rn0byl/CVE-2021-21551
    First seen May 21, 2021
    Open source ↗
  • GitHub PoCwaldo-irc/CVE-2021-21551
    First seen May 13, 2021

    Exploit to SYSTEM for CVE-2021-21551

    Open source ↗
  • Metasploitexploit/windows/local/cve_2021_21551_dbutil_memmove✓ verified
    First seen May 4, 2021

    Dell DBUtil_2_3.sys IOCTL memmove

    Open source ↗

Frequently asked(6)

What is CVE-2021-21551?
CVE-2021-21551 is a critical vulnerability published on May 4, 2021. Dell dbutil23.sys driver contains an insufficient access control vulnerability which may lead to escalation of privileges, denial of service, or information disclosure. Local authenticated user access is required.
When was CVE-2021-21551 disclosed?
CVE-2021-21551 was first published in the National Vulnerability Database on May 4, 2021, with the most recent update on October 28, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-21551 actively exploited?
Yes. CISA added CVE-2021-21551 to the Known Exploited Vulnerabilities catalog on March 31, 2022, affecting Dell dbutil Driver. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2021-21551?
CVE-2021-21551 has a CVSS v3 base score of 8.8 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0.
Which products are affected by CVE-2021-21551?
CVE-2021-21551 affects Dell dbutil Driver. The full affected-products list, including version ranges and fixed versions, is shown in the Affected Packages section of this page.
How do I remediate CVE-2021-21551?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-21551, 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

Explore the affected products and dependency analysis for CVE-2021-21551

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