{"id":"CVE-2021-30116","state":"PUBLISHED","title":"Unauthenticated credential leak and business logic flaw in Kaseya VSA <= v9.5.6","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.","publishedAt":"2021-07-09T00:00:00.000Z","updatedAt":"2026-08-14T03:55:30.740Z","severity":{"score":10,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","source":"mitre"},"assigner":"mitre","products":["n/a n/a"],"affected":[{"vendor":"n/a","product":"n/a","versions":[{"version":"n/a","status":"affected"}]}],"references":["https://csirt.divd.nl/2021/07/04/Kaseya-Case-Update-2/","https://helpdesk.kaseya.com/hc/en-gb/articles/4403440684689-Important-Notice-July-2nd-2021","https://csirt.divd.nl/2021/07/07/Kaseya-Limited-Disclosure/","https://www.secpod.com/blog/kaseya-vsa-zero-day-by-revil/","https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30116"],"weaknesses":["CWE-522"],"ingestedAt":"2026-10-29T19:48:26.823Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2021/30xxx/CVE-2021-30116.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2021-30116","state":"PUBLISHED","datePublished":"2021-07-09T00:00:00.000Z","dateUpdated":"2026-08-14T03:55:30.740Z","assignerShortName":"mitre","assignerOrgId":"8254265b-2729-46b6-b9e3-3dfca2d5bfca","dateReserved":"2021-04-02T00:00:00.000Z"},"containers":{"cna":{"title":"Unauthenticated credential leak and business logic flaw in Kaseya VSA <= v9.5.6","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"n/a","product":"n/a","versions":[{"version":"n/a","status":"affected"}]}],"references":[{"url":"https://csirt.divd.nl/2021/07/04/Kaseya-Case-Update-2/"},{"url":"https://helpdesk.kaseya.com/hc/en-gb/articles/4403440684689-Important-Notice-July-2nd-2021"},{"url":"https://csirt.divd.nl/2021/07/07/Kaseya-Limited-Disclosure/"},{"url":"https://www.secpod.com/blog/kaseya-vsa-zero-day-by-revil/"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH","baseScore":10,"baseSeverity":"CRITICAL"}}],"problemTypes":[{"descriptions":[{"type":"text","lang":"en","description":"n/a"}]}],"providerMetadata":{"shortName":"mitre","orgId":"8254265b-2729-46b6-b9e3-3dfca2d5bfca","dateUpdated":"2023-10-23T13:12:39.540Z"},"credits":[{"lang":"en","value":"Discovered by Wietse Boonstra of DIVD"},{"lang":"en","value":"Additional research by Frank Breedijk of DIVD"}],"x_generator":{"engine":"Vulnogram 0.0.9"},"source":{"advisory":"DIVD-2021-00011","discovery":"INTERNAL"},"solutions":[{"lang":"en","value":"Upgrade to a version after 9.5.6"}]},"adp":[{"title":"CVE Program Container","references":[{"url":"https://csirt.divd.nl/2021/07/04/Kaseya-Case-Update-2/","tags":["x_transferred"]},{"url":"https://helpdesk.kaseya.com/hc/en-gb/articles/4403440684689-Important-Notice-July-2nd-2021","tags":["x_transferred"]},{"url":"https://csirt.divd.nl/2021/07/07/Kaseya-Limited-Disclosure/","tags":["x_transferred"]},{"url":"https://www.secpod.com/blog/kaseya-vsa-zero-day-by-revil/","tags":["x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-03T22:24:59.326Z"}},{"title":"CISA ADP Vulnrichment","references":[{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30116","tags":["government-resource"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2021-07-06T00:00:00+00:00","options":[{"Exploitation":"active"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3","id":"CVE-2021-30116"}}},{"other":{"type":"kev","content":{"dateAdded":"2021-11-03","reference":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30116"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-522","lang":"en","type":"CWE","description":"CWE-522 Insufficiently Protected Credentials"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-14T03:55:30.740Z"},"timeline":[{"time":"2021-11-03T00:00:00.000Z","lang":"en","value":"CVE-2021-30116 added to CISA KEV"}]}]}}}