CVE intelligence

CVE-2023-42118

Vulnerability intelligence

Published May 3, 2024Sources checked Nov 1, 2026

8.8HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2023-42118 and is rated High severity with a CVSS score of 8.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Oct 21, 2026

Release Notes

Vendor-listed releases

0:1.2.11-19.20210922git4915c308.azl4

CISA KEVNot listedBased on the latest collected catalog

EPSS8.4%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2023-42118?

Exim libspf2 Integer Underflow Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of Exim libspf2.

Authentication is not required to exploit this vulnerability.

The specific flaw exists within the parsing of SPF macros. When parsing SPF macros, the process does not properly validate user-supplied data, which can result in an integer underflow before writing to memory.

An attacker can leverage this vulnerability to execute code in the context of the service account. . Was ZDI-CAN-17578.

Source: NVD