CVE-2026-66140 Path traversal in Exim
Attackers can traverse directories to access files outside the spool area and gain privileges due to mishandled queue-name arguments in Exim.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-66140?
CVE-2026-66140 is a high-severity path traversal vulnerability in Exim Exim, published on 24 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Exim before 4.99.5 allows directory traversal to access files outside of the spool area, and consequently gain privileges, because arguments related to queue-name are mishandled.
Weakness: CWE-24
Which versions are affected by CVE-2026-66140?
It affects 1 product.
Products include Exim Exim.
How do I fix CVE-2026-66140?
Upgrade to a fixed version.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-66140 being exploited?
There is no known exploitation of CVE-2026-66140 in the wild and no public exploit code.
Other vulnerabilities in Exim Exim
Sources
Also known as DEBIAN-CVE-2026-66140, GHSA-5qxf-w5v2-m3rg, ROOT-OS-DEBIAN-11-CVE-2026-66140, ROOT-OS-DEBIAN-12-CVE-2026-66140, UBUNTU-CVE-2026-66140.