SB2020110428 - Red Hat Enterprise Linux 8 update for dovecot



SB2020110428 - Red Hat Enterprise Linux 8 update for dovecot

Published: November 4, 2020

Security Bulletin ID SB2020110428
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 vulnerabilities.


1) Use-after-free (CVE-ID: CVE-2020-10958)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a use-after-free error when processing newline characters. A remote attacker can a specially crafted command to submission, submission-login or lmtp service and perform a denial of service (DoS) attack.


2) Input validation error (CVE-ID: CVE-2020-10967)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/U:Green


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input passed via email message. A remote attacker can send a specially crafted email with empty quoted localpart and crash the submission or lmtp service.

PoC:

Send mail with envelope sender or recipient as ``<""@example.org>``.

Remediation

Install update from vendor's website.