Cyber Resilience

CVE-2021-30121

MediumPublic PoC

Published: 09 July 2021

Published
09 July 2021
Modified
21 November 2024
KEV Added
Patch
07 July 2021
CVSS Score v3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0038 60.1th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-30121 is a medium-severity Inclusion of Functionality from Untrusted Control Sphere (CWE-829) vulnerability in Kaseya Vsa. Its CVSS base score is 6.5 (Medium).

Operationally, ranked in the top 39.9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Semi-authenticated local file inclusion The contents of arbitrary files can be returned by the webserver Example request: `https://x.x.x.x/KLC/js/Kaseya.SB.JS/js.aspx?path=C:\Kaseya\WebPages\dl.asp` A valid sessionId is required but can be easily obtained via CVE-2021-30118

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

kaseya
vsa
≤ 9.5.6

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-829

Limiting P2P file sharing technology reduces inclusion of functionality or resources from untrusted external control spheres.

addresses: CWE-829

Enforcing installation policies prevents users from including functionality obtained from untrusted control spheres.

addresses: CWE-829

The inventory process requires identifying and recording the origin of all components, making inclusion of functionality from untrusted control spheres easier to detect during reviews.

addresses: CWE-829

Requiring approval and monitoring of maintenance tools prevents inclusion and execution of functionality obtained from untrusted sources.

addresses: CWE-829

Unowned portable devices represent untrusted control spheres; the prohibition prevents inclusion of functionality or data from such sources.

addresses: CWE-829

Strategy mandates assessment of third-party components and suppliers, directly reducing inclusion of functionality from untrusted control spheres.

addresses: CWE-829

Procedures can mandate supply-chain vetting and restrictions on functionality obtained from untrusted third-party or external control spheres.

addresses: CWE-829

Requires use of trusted sources and provenance tracking, tangibly limiting inclusion of functionality from untrusted control spheres.

References