CVE-2021-30116VulnerabilityPublished 11/03/2021Updated 10/24/2026

CVE-2021-30116: Kaseya Virtual System/Server Administrator (VSA) Information Disclosure Vulnerability

Affects Kaseya Virtual System/Server Administrator (VSA)Source CISA KEV

Severity

High

No CVSS score published yet

Exploitation: Actively exploited – in CISA KEV since 11/03/2021
KEV deadline: 11/17/2021
Ransomware: Used in ransomware campaigns
EPSS: 85.7% chance of exploitation in 30 days – higher than 99% of CVEs

What to do

CISA required action

Apply updates per vendor instructions.

nvd.nist.gov/vuln/detail/CVE-2021-30116 (opens in a new tab)

Description

Kaseya Virtual System/Server Administrator (VSA) has an information disclosure vulnerability (CVE-2021-30116) that allows attackers to obtain session IDs. These session IDs can be leveraged to conduct further attacks against the system. The vulnerability has been exploited in the wild and is associated with known ransomware campaigns. No specific affected versions or patch information are provided.

Summary

CVE-2021-30116 is an information disclosure vulnerability in Kaseya Virtual System/Server Administrator (VSA) that permits an attacker to obtain session IDs. These session IDs can then be used to execute additional attacks on the system. The vulnerability is classified under CWE-522 (Insufficiently Protected Credentials). It has been exploited in the wild and linked to ransomware campaigns. No vendor advisory or patch information is available in the provided data.

Impact

An attacker who successfully exploits this vulnerability can obtain session IDs, which may allow unauthorized access or further compromise of the VSA system. This can lead to unauthorized actions within the system and has been leveraged in ransomware attacks, indicating significant operational and security impact.

Mitigation

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, limit exposure of the VSA system to untrusted networks and monitor for suspicious activity related to session handling.

Weaknesses

CWE-522Insufficiently Protected Credentials (opens in a new tab)

What to do

Description

AnalysisAI-generated, updated 10/24/2026, 09:20:24 UTC

Weaknesses

References

Related threats