{"cve":"CVE-2021-30120","nvd":{"published":"2021-07-09T14:15:07.903","modified":"2026-08-14T05:16:54.937","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","score":7.5},"cwes":["CWE-669"],"references":["https://csirt.divd.nl/2021/07/07/Kaseya-Limited-Disclosure/","https://csrit.divd.nl/CVE-2021-30120","https://csrit.divd.nl/DIVD-2021-00011","https://csirt.divd.nl/2021/07/07/Kaseya-Limited-Disclosure/","https://csrit.divd.nl/CVE-2021-30120"],"products":["kaseya:vsa"],"source":"nvd","synced_at":"2026-10-19T21:21:13.713336758+00:00"},"epss":{"cve":"CVE-2021-30120","score":0.05701,"percentile":0.93011,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}