Vulnerability in Kaseya Vsa
CVE-2021-30120
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.057 (92.7th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 93rd percentile — 92.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.057 · newest: 0.057 · change: 0.000
Affected products
Weakness classification (CWE)
References
- csirt.divd.nl/2021/07/07/Kaseya-Limited-Disclosure/ (Patch, Third Party Advisory)
- csrit.divd.nl/DIVD-2021-00011 (Permissions Required, Third Party Advisory)
- csrit.divd.nl/CVE-2021-30120 (Permissions Required, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-30120?
- CVE-2021-30120 is a critical-severity vulnerability in Kaseya Vsa, classified under Incorrect Resource Transfer Between Spheres. CVSS score: 9.9/10. Published 2021-07-09.
- How severe is CVE-2021-30120?
- Critical severity. CVSS v3 base score is 9.9 out of 10.