{"identifier":"CVE-2021-30116","cve":{"id":"CVE-2021-30116","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.","published":"2021-07-09T14:15:07.770000+00:00","modified":"2026-08-14T05:16:54.497000+00:00","status":"Analyzed","score":10.0,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","cvss_version":"3.1","affected":[{"criteria":"cpe:2.3:a:kaseya:vsa_agent:*:*:*:*:*:*:*:*","versionStartIncluding":"","versionStartExcluding":"","versionEndIncluding":"","versionEndExcluding":"9.5.0.24"},{"criteria":"cpe:2.3:a:kaseya:vsa_server:*:*:*:*:*:*:*:*","versionStartIncluding":"","versionStartExcluding":"","versionEndIncluding":"","versionEndExcluding":"9.5.7a"}],"weaknesses":["CWE-522"],"references":[{"url":"https://csirt.divd.nl/2021/07/04/Kaseya-Case-Update-2/","source":"cve@mitre.org","tags":["Third Party Advisory"]},{"url":"https://csirt.divd.nl/2021/07/07/Kaseya-Limited-Disclosure/","source":"cve@mitre.org","tags":["Third Party Advisory"]},{"url":"https://helpdesk.kaseya.com/hc/en-gb/articles/4403440684689-Important-Notice-July-2nd-2021","source":"cve@mitre.org","tags":["Vendor Advisory"]},{"url":"https://www.secpod.com/blog/kaseya-vsa-zero-day-by-revil/","source":"cve@mitre.org","tags":["Exploit","Third Party Advisory"]},{"url":"https://csirt.divd.nl/2021/07/04/Kaseya-Case-Update-2/","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Third Party Advisory"]},{"url":"https://csirt.divd.nl/2021/07/07/Kaseya-Limited-Disclosure/","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Third Party Advisory"]},{"url":"https://helpdesk.kaseya.com/hc/en-gb/articles/4403440684689-Important-Notice-July-2nd-2021","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Vendor 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instructions.","dueDate":"2021-11-17","knownRansomwareCampaignUse":"Known","forensicTriage":"No","notes":"https://nvd.nist.gov/vuln/detail/CVE-2021-30116","cwes":["CWE-522"]},"kev_checked":true,"metrics":{"cvssMetricV31":[{"source":"cve@mitre.org","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","baseScore":10.0,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":6.0},{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":9.8,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":5.9}],"cvssMetricV2":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"2.0","vectorString":"AV:N/AC:L/Au:N/C:P/I:P/A:P","baseScore":7.5,"accessVector":"NETWORK","accessComplexity":"LOW","authentication":"NONE","confidentialityImpact":"PARTIAL","integrityImpact":"PARTIAL","availabilityImpact":"PARTIAL"},"baseSeverity":"HIGH","exploitabilityScore":10.0,"impactScore":6.4,"acInsufInfo":false,"obtainAllPrivilege":false,"obtainUserPrivilege":false,"obtainOtherPrivilege":false,"userInteractionRequired":false}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2021-07-06T00:00:00+00:00","id":"CVE-2021-30116","options":[{"exploitation":"active"},{"automatable":"yes"},{"technicalImpact":"total"}],"role":"CISA 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