SB2021062150 - Ubuntu update for dovecot



SB2021062150 - Ubuntu update for dovecot

Published: June 21, 2021

Security Bulletin ID SB2021062150
Severity
Medium
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

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

Description

This security bulletin contains information about 2 secuirty vulnerabilities.


1) Path traversal (CVE-ID: CVE-2021-29157)

The vulnerability allows a local user to perform directory traversal attacks.

The vulnerability exists due to validation of kid and azp fields in JWT tokens. A local user to ability to control a JWT token location can login as any MTA user and access their emails.


2) Code injection (CVE-ID: CVE-2021-33515)

The vulnerability allows a remote attacker to gain access to sensitive information.

The vulnerability exists in the way STARTTLS command in processed by the SMTP server. the commands sent during the session before the STARTTLS command are queued and executed later, after the STARTTLS finished with the client. As a result, a remote attacker can perform a MitM attack and gain access to victim's emails.


Remediation

Install update from vendor's website.