High CVSS 8.8

Overview

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.

Risk analysis

This vulnerability is rated 🟠 HIGH.

  • CVSS: 8.8 (HIGH)
  • Detected tags: int_overflow, rce (tag impact: VERY HIGH)

Recommended actions:

  • Patch/upgrade immediately (remote code execution).
  • Reduce exposure (WAF/segmentation), minimize attack surface.

Recommended tools

Tags