CVE-2021-20016

CRITICALNVD 9.89.8—
EchelonGraph scoreHIGH confidence

Score elevated to 9.8 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 9.8 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
9.8EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS PROB: 37%CVSS: 9.8Exploit: cisa kev · ssvc active · kev ransomware · epss top5pctExposed: 0

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

A SQL-Injection vulnerability in the SonicWall SSLVPN SMA100 product allows a remote unauthenticated attacker to perform SQL query to access username password and other session related information. This vulnerability impacts SMA100 build version 10.x.

CVSS v3
9.8
EG Score
9.8(high)
EG Risk
99(Act)
EG Risk 99/100SSVC: Act

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
Severity98% × 45%
Exploitation100% × 40%
Automatability100% × 15%
Action: Fix now — active exploitation, automatable, high impact.
EPSS PROB
37%
EPSS %ILE
98%
KEV
⚠ Exploited

Published

February 4, 2021

Last Modified

August 12, 2026

Advisory Details (2)

Auto-updated Aug 19, 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-2021-20016
generic

Security Advisory

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0001

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 59× in last 7d / 218× 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 627 total refreshes for this CVE.

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

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Frequently asked(6)

What is CVE-2021-20016?
CVE-2021-20016 is a critical vulnerability published on February 4, 2021. A SQL-Injection vulnerability in the SonicWall SSLVPN SMA100 product allows a remote unauthenticated attacker to perform SQL query to access username password and other session related information. This vulnerability impacts SMA100 build version 10.x.
When was CVE-2021-20016 disclosed?
CVE-2021-20016 was first published in the National Vulnerability Database on February 4, 2021, with the most recent update on August 12, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-20016 actively exploited?
Yes. CISA added CVE-2021-20016 to the Known Exploited Vulnerabilities catalog on November 3, 2021, affecting SonicWall SSLVPN SMA100. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2021-20016?
CVE-2021-20016 has a CVSS v3 base score of 9.8 (NVD).
Which products are affected by CVE-2021-20016?
CVE-2021-20016 affects SonicWall SSLVPN SMA100. 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-2021-20016?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-20016, 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

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