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vulnerability

Ubuntu: USN-6411-1 (CVE-2023-42115): Exim vulnerabilities

Severity
10
CVSS
(AV:N/AC:L/Au:N/C:C/I:C/A:C)
Published
Oct 4, 2023
Added
Oct 6, 2023
Modified
Apr 16, 2026

Description

Exim AUTH Out-Of-Bounds Write Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Exim. Authentication is not required to exploit this vulnerability.

The specific flaw exists within the smtp service, which listens on TCP port 25 by default. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of a buffer. An attacker can leverage this vulnerability to execute code in the context of the service account.
. Was ZDI-CAN-17434.

Solutions

ubuntu-pro-upgrade-exim4ubuntu-pro-upgrade-exim4-baseubuntu-pro-upgrade-exim4-daemon-heavyubuntu-pro-upgrade-exim4-daemon-lightubuntu-pro-upgrade-eximon4ubuntu-upgrade-exim4ubuntu-upgrade-exim4-baseubuntu-upgrade-exim4-daemon-heavyubuntu-upgrade-exim4-daemon-lightubuntu-upgrade-eximon4
Title
Rapid7 Labs

2026 Global Threat Landscape Report

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