{"cve_id":"CVE-2021-30116","published":"2021-07-09T14:15:07.770000+00:00","last_modified":"2026-08-14T05:16:54.497000+00:00","vuln_status":"Analyzed","description":"Kaseya VSA before 9.5.7 allows credential disclosure, as exploited in the wild in July 2021. By default Kaseya VSA on premise offers a download page where the clients for the installation can be downloaded. The default URL for this page is https://x.x.x.x/dl.asp When an attacker download a client for Windows and installs it, the file KaseyaD.ini is generated (C:\\Program Files (x86)\\Kaseya\\XXXXXXXXXX\\KaseyaD.ini) which contains an Agent_Guid and AgentPassword This Agent_Guid and AgentPassword can be used to log in on dl.asp (https://x.x.x.x/dl.asp?un=840997037507813&pw=113cc622839a4077a84837485ced6b93e440bf66d44057713cb2f95e503a06d9) This request authenticates the client and returns a sessionId cookie that can be used in subsequent attacks to bypass authentication. Security issues discovered --- * Unauthenticated download page leaks credentials * Credentials of agent software can be used to obtain a sessionId (cookie) that can be used for services not intended for use by agents * dl.asp accepts credentials via a GET request * Access to KaseyaD.ini gives an attacker access to sufficient information to penetrate the Kaseya installation and its clients. Impact --- Via the page /dl.asp enough information can be obtained to give an attacker a sessionId that can be used to execute further (semi-authenticated) attacks against the system.","cvss_version":"3.1","cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","base_score":9.8,"base_severity":"CRITICAL","attack_vector":"NETWORK","privileges_req":"NONE","user_interaction":"NONE","scope":"UNCHANGED","impact_c":"HIGH","impact_i":"HIGH","impact_a":"HIGH","cwe_ids":["CWE-522"],"in_kev":true,"kev_date_added":"2021-11-03","kev_ransomware":true,"epss_score":0.85735,"epss_percentile":0.99726,"cap_rule_version":"0.1.1","stage":"INITIAL_ACCESS","req_access":"NONE","req_vector":"NETWORK","req_user_interaction":false,"grant_access":"USER","caps":["CODE_EXEC","CRED_ACCESS","INFO_DISCLOSURE"],"terminal":false,"cap_confidence":"high","ingested_at":"2026-09-18T09:46:15.678744+00:00","first_seen":"2021-07-09T14:15:07.770000+00:00","kev_first_seen":"2021-11-03T00:00:00+00:00","novelty_score":0.0,"novelty_reasons":[],"novelty_at":null,"vendors":["kaseya"],"products":["vsa_agent","vsa_server"],"affected":[{"vendor":"kaseya","product":"vsa_agent","ranges":["< 9.5.0.24"]},{"vendor":"kaseya","product":"vsa_server","ranges":["< 9.5.7a"]}]}