Vulnerability · Published Mar 27, 2026 · Assigned by OX
CVE-2026-0394
Medium 5.3
In plain English
A medium-severity path traversal in OX Dovecot Pro from Open-Xchange GmbH. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 38% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
When dovecot has been configured to use per-domain passwd files, and they are placed one path component above /etc, or slash has been added to allowed characters, path traversal can happen if the domain component is directory partial. This allows inadvertently reading /etc/passwd (or some other path which ends with passwd). If this file contains passwords, it can be used to authenticate wrongly, or if this is userdb, it can unexpectly make system users appear valid users. Upgrade to fixed version, or use different authentication scheme that does not rely on paths. Alternatively you can also ensure that the per-domain passwd files are in some other location, such as /etc/dovecot/auth/%d. No publicly available exploits are known.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | dovecot | 1:2.3.19.1+dfsg1-2.1+deb12u2 | DEBIAN-CVE-2026-0394 |
| Debian:13 | dovecot | 1:2.4.1+dfsg1-1 | DEBIAN-CVE-2026-0394 |
| Debian:14 | dovecot | 1:2.4.1+dfsg1-1 | DEBIAN-CVE-2026-0394 |
| Ubuntu:22.04:LTS | dovecot | 1:2.3.16+dfsg1-3ubuntu2.8 | USN-8136-2 |
| Ubuntu:22.04:LTS | dovecot | 1:2.3.16+dfsg1-3ubuntu2.7 | UBUNTU-CVE-2026-0394 |
| Ubuntu:24.04:LTS | dovecot | 1:2.3.21+dfsg1-2ubuntu6.4 | USN-8136-2 |
| Ubuntu:24.04:LTS | dovecot | 1:2.3.21+dfsg1-2ubuntu6.3 | UBUNTU-CVE-2026-0394 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Open-Xchange GmbH | OX Dovecot Pro | 0 – through 2.3.0 |
Weakness: CWE-22 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N