CVE-2021-30116

Kaseya Virtual System/Server Administrator (VSA) Information Disclosure Vulnerability

Severity: critical
CVSS v3: 10
EPSS percentile: 100%
Known exploited: yes (CISA KEV)
Vendor: Kaseya
Product: Virtual System/Server Administrator (VSA)
Published: 2021-11-03
Modified: 2026-08-14

Description

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 discovere

NVD record

Informational only. Not a warranty of security, completeness or fitness for any purpose. Derived from NVD, CISA KEV, FIRST.org EPSS and vendor advisories (CVE Program List v5); those sources change continuously and may be incomplete or incorrect. Verify every remediation against the vendor advisory before acting. Absence of a finding is not evidence that no vulnerability exists. Not endorsed by NVD, CISA, FIRST or any vendor named.

Raw record

{
  "id": "CVE-2021-30116",
  "title": "Kaseya Virtual System/Server Administrator (VSA) Information Disclosure Vulnerability",
  "description": "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 discovere",
  "severity": "critical",
  "cvss": 10,
  "epss": 100,
  "kev": 1,
  "vendor": "Kaseya",
  "product": "Virtual System/Server Administrator (VSA)",
  "published": "2021-11-03",
  "modified": "2026-08-14T05:16:54.497",
  "source": "nvd",
  "remediation": [],
  "disclaimer": "Informational only. Not a warranty of security, completeness or fitness for any purpose. Derived from NVD, CISA KEV, FIRST.org EPSS and vendor advisories (CVE Program List v5); those sources change continuously and may be incomplete or incorrect. Verify every remediation against the vendor advisory before acting. Absence of a finding is not evidence that no vulnerability exists. Not endorsed by NVD, CISA, FIRST or any vendor named."
}