SB2020022456 - Fedora 31 update for opensmtpd

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Main Vulnerability Database SB2020022456

SB2020022456 - Fedora 31 update for opensmtpd

Published: February 24, 2020 Updated: April 25, 2025

Security Bulletin ID SB2020022456
CSH 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 vulnerabilities.


1) Out-of-bounds read (CVE-ID: CVE-2020-8794)

CWE-ID: CWE-125 - Out-of-bounds read

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


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

The vulnerability exists due to a boundary condition in mta_io() function in mta_session.c for multi-line replies during mail delivery. A remote attacker can use a mail server to send specially crafted replies, trigger out-of-bounds read error and read contents of memory on the system.


2) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2020-8793)

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

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


The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to the application does not drop privileges when executing the "/usr/sbin/smtpctl" application with  a "-bi" command-line argument. A local user can leverage this behavior and use a specially crafted hardlink to execute arbitrary code on the system with elevated privileges.


Remediation

Install update from vendor's website.

References