CVE-2020-4020

Severity: high (CVSS 7.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-06-01 · updated 2026-06-17

Description

The file downloading functionality in the Atlassian Companion App before version 1.0.0 allows remote attackers, who control a Confluence Server instance that the Companion App is connected to, execute arbitrary .exe files via a Protection Mechanism Failure.

Affected products

Atlassian Companion App: before 1.0.0 — fixed in 1.0.0

How to fix

Upgrade to a fixed version: Atlassian Companion App 1.0.0. Check the vendor advisory for mitigations.

References

https://jira.atlassian.com/browse/CONFSERVER-59733
https://jira.atlassian.com/browse/CONFSERVER-59733

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