CVE-2021-21551

HIGHNVD 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
8.8
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS: 58%CVSS: 8.8Exploit: NoneExposed: 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)
EPSS
99.0%
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 / 224× 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 409 total refreshes for this CVE.

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

Publicly available exploits

(9 references)

Working exploit code is in the public domain (1 Metasploit module) (7 GitHub PoCs) (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • 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 ↗

Related CVEs(same CWE)

Frequently asked(6)

What is CVE-2021-21551?
CVE-2021-21551 is a high 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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