CVE-2018-20753

CRITICAL9.8

CISA KEV

Published 2019-02-05 · Updated 2026-08-13 · Source cve@mitre.org

Summary

CVE-2018-20753 is a critical-severity (CVSS 9.8) vulnerability in Kaseya Virtual System/Server Administrator (VSA). CISA added it to the Known Exploited Vulnerabilities catalog on April 13, 2022, which means exploitation in the wild has been confirmed; US federal agencies had to remediate it by May 4, 2022. CISA also lists it as known to be used in ransomware campaigns, so it should be prioritised accordingly. Kaseya has 3 vulnerabilities in the KEV catalog, 3 of them linked to ransomware.

All 3 known-exploited Kaseya vulnerabilities →

Description

Kaseya VSA RMM before R9.3 9.3.0.35, R9.4 before 9.4.0.36, and R9.5 before 9.5.0.5 allows unprivileged remote attackers to execute PowerShell payloads on all managed devices. In January 2018, attackers actively exploited this vulnerability in the wild.

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA Known-Exploited Vulnerability

Product: Kaseya — Virtual System/Server Administrator (VSA)

Name: Kaseya VSA Remote Code Execution Vulnerability

Date added: 2022-04-13 · Due: 2022-05-04

USED IN RANSOMWARE

Required action: Apply updates per vendor instructions.

References

View on NVD

More exploited Kaseya vulnerabilities

Most recently added to CISA KEV

CVE-2017-18362
RANSOMWARE
Virtual System/Server Administrator (VSA) — Kaseya VSA SQL Injection Vulnerability
added 2022-05-24
CVE-2021-30116
RANSOMWARE
Virtual System/Server Administrator (VSA) — Kaseya Virtual System/Server Administrator (VSA) Information Disclosure Vulnerability
added 2021-11-03

View all →

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