CVE-2021-30120
CRITICAL EXPLOITED IN THE WILD RANSOMWAREKaseya VSA <9.5.7 - Auth Bypass
Title source: llmDescription
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.
Scores
CVSS v3
9.9
EPSS
0.0041
EPSS Percentile
61.5%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Details
VulnCheck KEV
2021-07-06
InTheWild.io
2021-07-12
Ransomware Use
Confirmed
CWE
CWE-669
Status
published
Products (1)
kaseya/vsa
< 9.5.6
Published
Jul 09, 2021
Tracked Since
Feb 18, 2026