SB2020051424 - Amazon Linux AMI update for dovecot 



SB2020051424 - Amazon Linux AMI update for dovecot

Published: May 14, 2020

Security Bulletin ID SB2020051424
Severity
Medium
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

Medium 50% Low 50%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 secuirty vulnerabilities.


1) Authentication bypass (CVE-ID: CVE-2019-3814)

The vulnerability allows a remote authenticated attacker to bypass authentication.

The weakness exists due to taking of the username from the user provided authentication fields (e.g. LOGIN command). A remote attacker with access to a valid trusted certificate without the ssl_cert_username_field in it can bypass password verification if the provided trusted SSL certificate is missing the username field and login as anyone else in the system

2) Stack-based buffer overflow (CVE-ID: CVE-2019-7524)

The vulnerability allows a local user to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when reading FTS or POP3-UIDL header from dovecot index. A local user can modify Dovecot index, trigger stack-based buffer overflow and execute arbitrary code on the target system with privileges of the Dovecot process.


Remediation

Install update from vendor's website.