CVE-2021-30120
CriticalCVSS 9.9Exploitation Probability (EPSS)
Very high risk92th percentile - higher than 92% of all known CVEs
Summary
Kaseya VSA before 9.5.7 allows attackers to bypass the 2FA requirement. The 2FA check is enforced client-side instead of server-side and can be bypassed using a local proxy.
Risk Assessment
Bypassing 2FA renders the mechanism useless, increasing the risk of unauthorized access to user accounts and the VSA system.
Recommendation
Upgrade Kaseya VSA to 9.5.7 or later. Ensure 2FA verification is enforced server-side.
Other vulnerabilities in Kaseya VSA
See all- CVE-2021-30116CriticalActively exploited
Kaseya VSA before 9.5.7 allows credential disclosure. The default download page (dl.asp) is unauthenticated and generates KaseyaD.ini with Agent_Guid and AgentPassword, which can be used to obtain a sessionId and bypass authentication.
- CVE-2018-20753CriticalActively exploited
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.
- CVE-2017-18362CriticalActively exploited
ConnectWise ManagedITSync integration through 2017 for Kaseya VSA is vulnerable to unauthenticated remote commands that allow full direct access to the Kaseya VSA database. In February 2019, attackers have actively exploited this in the wild to download and execute ransomware payloads on all endpoints managed by the VSA server. If the ManagedIT.asmx page is available via the Kaseya VSA web interface, anyone with access to the page is able to run arbitrary SQL queries, both read and write, without authentication.
Original NVD description (English source)
Kaseya VSA before 9.5.7 allows attackers to bypass the 2FA requirement. The need to use 2FA for authentication in enforce client-side instead of server-side and can be bypassed using a local proxy. Thus rendering 2FA useless. Detailed description --- During the login process, after the user authenticates with username and password, the server sends a response to the client with the booleans MFARequired and MFAEnroled. If the attacker has obtained a password of a user and used an intercepting proxy (e.g. Burp Suite) to change the value of MFARequered from True to False, there is no prompt for the second factor, but the user is still logged in.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS