CVE-2021-42133

Name: CVE-2021-42133
Creator: NVD / NIST
Published: 2021-12-07T14:15:09.553+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.1/10EPSS 2.80%

Last modified Jun 17, 2026

CVE-2021-42133 is a high-severity vulnerability rated 8.1/10 on the CVSS scale. 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.. EPSS estimates a 2.80% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

8.1/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

EPSS Probability

2.80%

84.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Ivanti	Avalanche	< 6.3.3

References

https://forums.ivanti.com/s/article/Security-Alert-CVE-s-Addressed-in-Avalanche-6-3-3Vendor Advisory
https://forums.ivanti.com/s/article/Security-Alert-CVE-s-Addressed-in-Avalanche-6-3-3Vendor Advisory

Timeline

Published: Dec 7, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-42133?

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.

How severe is CVE-2021-42133?

CVE-2021-42133 has a CVSS score of 8.1/10 (HIGH severity). The EPSS model estimates a 2.80% probability of exploitation in the next 30 days.

How do I fix CVE-2021-42133?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-42133?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST