CVE-2021-30116

CRITICALNVD 10.010.0—
EchelonGraph scoreHIGH confidence

Score elevated to 10.0 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 10.0 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
10.0
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS: 86%CVSS: 10.0Exploit: NoneExposed: 0

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

Kaseya VSA before 9.5.7 allows credential disclosure, as exploited in the wild in July 2021. By default Kaseya VSA on premise offers a download page where the clients for the installation can be downloaded. The default URL for this page is https://x.x.x.x/dl.asp When an attacker download a client for Windows and installs it, the file KaseyaD.ini is generated (C:\Program Files (x86)\Kaseya\XXXXXXXXXX\KaseyaD.ini) which contains an Agent_Guid and AgentPassword This Agent_Guid and AgentPassword can be used to log in on dl.asp (https://x.x.x.x/dl.asp?un=840997037507813&pw=113cc622839a4077a84837485ced6b93e440bf66d44057713cb2f95e503a06d9) This request authenticates the client and returns a sessionId cookie that can be used in subsequent attacks to bypass authentication. Security issues discovered --- * Unauthenticated download page leaks credentials * Credentials of agent software can be used to obtain a sessionId (cookie) that can be used for services not intended for use by agents * dl.asp accepts credentials via a GET request * Access to KaseyaD.ini gives an attacker access to sufficient information to penetrate the Kaseya installation and its clients. Impact --- Via the page /dl.asp enough information can be obtained to give an attacker a sessionId that can be used to execute further (semi-authenticated) attacks against the system.

CVSS v3
10.0
EG Score
10.0(high)
EG Risk
100(Act)
EG Risk 100/100SSVC: 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
Severity100% × 45%
Exploitation100% × 40%
Automatability100% × 15%
Action: Fix now — active exploitation, automatable, high impact.
EPSS
99.7%
KEV
⚠ Exploited

Published

July 9, 2021

Last Modified

November 10, 2025

Advisory Details (4)

Auto-updated Jul 18, 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-2021-30116
generic

Kaseya’s Virtual System/Server Administrator (VSA) Zero-Day Under Acti | SecPod

https://www.secpod.com/blog/kaseya-vsa-zero-day-by-revil/
generic

Kaseya VSA Limited Disclosure | DIVD CSIRT

https://csirt.divd.nl/2021/07/07/Kaseya-Limited-Disclosure/
generic

Kaseya Case Update 2 | DIVD CSIRT

https://csirt.divd.nl/2021/07/04/Kaseya-Case-Update-2/

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 41× in last 7d / 204× 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 422 total refreshes for this CVE.

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

Publicly available exploits

(1 reference)

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

  • Nucleihttp/cves/2021/CVE-2021-30116.yaml
    First seen Jan 1, 2021

    Kaseya VSA < 9.5.7 - Credential Disclosure via Windows Agent

    Open source ↗

Related CVEs(same CWE)

Frequently asked(6)

What is CVE-2021-30116?
CVE-2021-30116 is a critical vulnerability published on July 9, 2021. Kaseya VSA before 9.5.7 allows credential disclosure, as exploited in the wild in July 2021. By default Kaseya VSA on premise offers a download page where the clients for the installation can be downloaded. The default URL for this page is https://x.x.x.x/dl.asp When an attacker download a client…
When was CVE-2021-30116 disclosed?
CVE-2021-30116 was first published in the National Vulnerability Database on July 9, 2021, with the most recent update on November 10, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-30116 actively exploited?
Yes. CISA added CVE-2021-30116 to the Known Exploited Vulnerabilities catalog on November 3, 2021, affecting Kaseya Virtual System/Server Administrator (VSA). KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2021-30116?
CVE-2021-30116 has a CVSS v3 base score of 10.0 (NVD).
Which products are affected by CVE-2021-30116?
CVE-2021-30116 affects Kaseya Virtual System/Server Administrator (VSA). 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-2021-30116?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-30116, 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-2021-30116

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