Description
An attacker that can get Dovecot to relay a message, for example through Sieve redirect or submission relay, can use a crafted line ending in the message body to bypass the outbound protection that prevents message content from being interpreted as SMTP commands. A downstream mail server that hasn't yet fixed the SMTP smuggling vulnerability can be tricked into treating part of the message body as new SMTP commands, allowing injection of spoofed email. This is the same vulnerability class as CVE-2023-51764 and CVE-2023-51766. Where you control the receiving mail servers, ensure they reject bare carriage returns in message data. Update to non-vulnerable version. No publicly available exploits are known.
No analysis available yet.
Remediation
No remediation available yet.
Tracking
Sign in to view the affected projects.
Advisories
No advisories yet.
References
History
Fri, 28 Aug 2026 11:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | An attacker that can get Dovecot to relay a message, for example through Sieve redirect or submission relay, can use a crafted line ending in the message body to bypass the outbound protection that prevents message content from being interpreted as SMTP commands. A downstream mail server that hasn't yet fixed the SMTP smuggling vulnerability can be tricked into treating part of the message body as new SMTP commands, allowing injection of spoofed email. This is the same vulnerability class as CVE-2023-51764 and CVE-2023-51766. Where you control the receiving mail servers, ensure they reject bare carriage returns in message data. Update to non-vulnerable version. No publicly available exploits are known. | |
| Weaknesses | CWE-655 | |
| References |
| |
| Metrics |
cvssV3_1
|
Subscriptions
No data.
Status: PUBLISHED
Assigner: OX
Published:
Updated: 2026-08-28T10:30:33.647Z
Reserved: 2026-03-23T12:58:38.266Z
Link: CVE-2026-33604
No data.
Status : Received
Published: 2026-08-28T12:16:27.613
Modified: 2026-08-28T12:16:27.613
Link: CVE-2026-33604
No data.
OpenCVE Enrichment
No data.
Weaknesses
-
CWE-655
Insufficient Psychological Acceptability