CVE-2021-30116 — Kaseya VSA before 9

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

01What is this vulnerability?

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…

02Affected products

No structured affected-product list available — see references below for vendor advisories.

03Active exploitation status

Yes — actively exploited. Added to the CISA KEV catalog on 2021-11-03. Ransomware use: Known.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

Open in Sigma generator →

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2021-07-09T14:15:07.770
• Last modified: 2026-08-14T05:16:54.497
• Added to CISA KEV: 2021-11-03

09References

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