CWE-655

Insufficient Psychological Acceptability

The product has a protection mechanism that is too difficult or inconvenient to use, encouraging non-malicious users to disable or bypass the mechanism, whether by accident or on purpose.

CVE-2026-33604 (GCVE-0-2026-33604)
Vulnerability from cvelistv5
Published
2026-08-28 10:12
Modified
2026-08-28 15:55
CWE
  • CWE-655 - Insufficient Psychological Acceptability
Summary
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.
Impacted products
Vendor Product Version
Open-Xchange GmbH OX Dovecot Pro Version: 2.3.0   
Version: 3.0.0   
Version: 3.1.0   
Create a notification for this product.
Show details on NVD website


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Mitigation

Phase: Testing

Description:

  • Where possible, perform human factors and usability studies to identify where your product's security mechanisms are difficult to use, and why.
Mitigation

Phase: Architecture and Design

Description:

  • Make the security mechanism as seamless as possible, while also providing the user with sufficient details when a security decision produces unexpected results.

No CAPEC attack patterns related to this CWE.

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