CVE-2026-94054 Memory corruption in Exim
An out-of-bounds write in Exim allows code execution when Proxy-Protocol is used with a malicious proxy.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-94054?
CVE-2026-94054 is a high-severity memory corruption vulnerability in Exim Exim, published on 19 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Exim before 4.100.1, when Proxy-Protocol is used with an attacker-controlled proxy, has an out-of-bounds write.
Weakness: CWE-787
Which versions are affected by CVE-2026-94054?
It affects 1 product.
Products include Exim Exim.
How do I fix CVE-2026-94054?
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-2026-94054 being exploited?
There is no known exploitation of CVE-2026-94054 in the wild and no public exploit code.
Other vulnerabilities in Exim Exim
Sources
Also known as CLSA-2026-1790290858, CLSA-2026-1790290861, CLSA-2026-1791401562, DEBIAN-CVE-2026-94054, GHSA-r24f-7cqq-88w4, ROOT-OS-DEBIAN-12-CVE-2026-94054 and 1 more.