CVE-2020-28019 Denial of service in n/a
An attacker can cause a denial of service in Exim mail servers by triggering stack consumption via improper initialization during BDAT command processing.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2020-28019?
CVE-2020-28019 is a high-severity denial of service 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 Initialization that can lead to recursion-based stack consumption or other consequences. This occurs because use of certain getc functions is mishandled when a client uses BDAT instead of DATA.
Weakness: CWE-665
Which versions are affected by CVE-2020-28019?
It affects 1 product.
Products include Exim Exim.
How do I fix CVE-2020-28019?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2020-28019 being exploited?
There is no known exploitation of CVE-2020-28019 in the wild and no public exploit code.
Other vulnerabilities in Exim Exim
Sources
Also known as CLEANSTART-2025-US94086, DEBIAN-CVE-2020-28019, GHSA-vxgq-8r56-c922, UBUNTU-CVE-2020-28019.