CVE-2020-28011 Memory corruption in n/a

High 7.8 Published 6 May 2021 Updated 4 Aug 2024

Heap-based buffer overflow in Exim allows local attackers to escalate privileges from the exim user to root.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2020-28011?

CVE-2020-28011 is a high-severity memory corruption vulnerability in Exim Exim, published on 6 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Exim 4 before 4.94.2 allows Heap-based Buffer Overflow in queue_run via two sender options: -R and -S. This may cause privilege escalation from exim to root.

Weakness: CWE-787

Which versions are affected by CVE-2020-28011?

It affects 1 product.

Products include Exim Exim.

How do I fix CVE-2020-28011?

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-2020-28011 being exploited?

There is no known exploitation of CVE-2020-28011 in the wild and no public exploit code.

All Exim Exim vulnerabilities

Sources

Also known as CLEANSTART-2025-DA82799, DEBIAN-CVE-2020-28011, GHSA-j622-pr6m-cmfr, UBUNTU-CVE-2020-28011.