CVE-2020-5239: Unspecified vulnerability in the fetchmail script in Mailu

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-02-13 · updated 2026-06-17
Weakness: CWE-863

Description

In Mailu before version 1.7, an authenticated user can exploit a vulnerability in Mailu fetchmail script and gain full access to a Mailu instance. Mailu servers that have open registration or untrusted users are most impacted. The master and 1.7 branches are patched on our git repository. All Docker images published on docker.io/mailu for tags 1.5, 1.6, 1.7 and master are patched. For detailed instructions about patching and securing the server afterwards, see https://github.com/Mailu/Mailu/issues/1354

Affected products

Mailu: before 1.7 — fixed in 1.7

How to fix

Upgrade to a fixed version: Mailu 1.7. Check the vendor advisory for mitigations.

References

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