CVE-2025-59032 Denial of service in OX Dovecot Pro
Attackers can crash the ManageSieve service by sending a malformed AUTHENTICATE command, causing denial of service for legitimate users.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-59032?
CVE-2025-59032 is a high-severity denial of service vulnerability in Dovecot Dovecot, published on 27 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
ManageSieve AUTHENTICATE command crashes when using literal as SASL initial response. This can be used to crash ManageSieve service repeatedly, making it unavailable for other users. Control access to ManageSieve port, or disable the service if it's not needed. Alternatively upgrade to a fixed version. No publicly available exploits are known.
Which versions are affected by CVE-2025-59032?
It affects 2 products.
Products include Dovecot Dovecot, Open-Xchange Dovecot.
How do I fix CVE-2025-59032?
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-2025-59032 being exploited?
There is no known exploitation of CVE-2025-59032 in the wild and no public exploit code.
Other vulnerabilities in Dovecot Dovecot
Sources
Also known as AZL-81692, DEBIAN-CVE-2025-59032, GHSA-w2gj-cmfm-c4j4, UBUNTU-CVE-2025-59032.