CVE-2025-59028
Medium · 5.3CVSS
5.3
EPSS
0.4%
Published
Mar 27, 2026
CISA due date
—
The record
When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. Install fixed version or disable concurrency in login processes (heavy perfomance penalty on large deployments). No publicly available exploits are known.
Affected packages
| Ecosystem | Package | Introduced | Fixed |
|---|---|---|---|
| openSUSE:Leap 16.0 | dovecot24 | 0 | 2.4.3-160000.1.1 |
| openSUSE:Tumbleweed | dovecot24 | 0 | 2.4.3-1.1 |
Related vulnerabilities
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