CVE-2020-28022 Memory corruption in n/a

Critical 9.8 Published 6 May 2021 Updated 4 Aug 2024

Exim mail server contains a memory corruption vulnerability in MAIL FROM and RCPT TO processing, potentially allowing remote code execution or denial of service.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2020-28022?

CVE-2020-28022 is a critical memory corruption vulnerability in Exim Exim, published on 6 May 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Exim 4 before 4.94.2 has Improper Restriction of Write Operations within the Bounds of a Memory Buffer. This occurs when processing name=value pairs within MAIL FROM and RCPT TO commands.

Weakness: CWE-787

Which versions are affected by CVE-2020-28022?

It affects 1 product.

Products include Exim Exim.

How do I fix CVE-2020-28022?

Upgrade to a fixed version.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2020-28022 being exploited?

There is no known exploitation of CVE-2020-28022 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

All Exim Exim vulnerabilities

Sources

Also known as CLEANSTART-2025-NF45930, DEBIAN-CVE-2020-28022, GHSA-j453-4grx-f82g, UBUNTU-CVE-2020-28022.