# CVE-2021-30116

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.

- Page: https://www.vulneraibility.com/cve/CVE-2021-30116
- CVSS: 10.0
- Known exploited: yes, in CISA KEV since 2021-11-03; CISA due date 2021-11-17; known ransomware use
- EPSS: 85.73% (percentile 99.7)
- Detection templates only, no public exploit found: 1 Nuclei template
- CISA SSVC: exploitation active, automatable yes, technical impact total (assessed 2021-07-06)
- Weakness: CWE-522
- Published: 2021-07-09

## Affected

- kaseya:vsa_agent
- kaseya:vsa_server

## References

- [other] https://csirt.divd.nl/2021/07/04/Kaseya-Case-Update-2/
- [other] https://helpdesk.kaseya.com/hc/en-gb/articles/4403440684689-Important-Notice-July-2nd-2021
- [other] https://csirt.divd.nl/2021/07/07/Kaseya-Limited-Disclosure/
- [other] https://www.secpod.com/blog/kaseya-vsa-zero-day-by-revil/
- [other] https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30116

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.