Cyber Resilience

CVE-2021-42133

High

Published: 07 December 2021

Published
07 December 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 8.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
EPSS Score 0.1440 94.6th percentile
Risk Priority 25 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-42133 is a high-severity Unrestricted Upload of File with Dangerous Type (CWE-434) vulnerability in Ivanti Avalanche. Its CVSS base score is 8.1 (High).

Operationally, ranked in the top 5.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

An exposed dangerous function vulnerability exists in Ivanti Avalanche before 6.3.3 allows an attacker with access to the Inforail Service to perform an arbitrary file write.

CWE(s)

Related Threats

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

Affected Assets

ivanti
avalanche
≤ 6.3.3

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-434 CWE-829

Requiring identifiable owners for portable devices reduces the attack surface for unrestricted uploads of dangerous file types via anonymous media.

addresses: CWE-829 CWE-434

Isolated execution prevents functionality from an untrusted sphere from affecting the real environment, allowing safe behavioral inspection.

addresses: CWE-434 CWE-829

Scans files from external sources on download/open/execute, blocking unrestricted uploads of dangerous file types.

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

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

References