Signature Detail

SMTP: Dovecot Submission-Login Service NULL Pointer Dereference

This signature detects attempts to exploit a known vulnerability against Dovecot server. The vulnerability is due to a NULL pointer dereference in the submission-login service when authentication is aborted. A remote attacker could exploit this vulnerability by sending malicious requests to a targeted server. Successful exploitation will cause the Dovecot submission-login process to abnormally terminate. By repeatedly sending such crafted requests, the attacker may effect a partial denial-of-service.

Extended Description

In the IMAP Server in Dovecot 2.3.3 through 2.3.5.2, the submission-login service crashes when the client disconnects prematurely during the AUTH command.

Affected Products

• Dovecot dovecot 2.3.3
• Dovecot dovecot 2.3.4
• Dovecot dovecot 2.3.4.1
• Dovecot dovecot 2.3.5
• Dovecot dovecot 2.3.5.1
• Dovecot dovecot 2.3.5.2

References

• CVE: CVE-2019-11494