In Apache SpamAssassin before 3.4.3, nefarious CF files can be configured to run system commands without any output or errors. With this, exploits can be injected in a number of scenarios. In addition to upgrading to SA 3.4.3, we recommend that users should only use update channels or 3rd party .cf files from trusted places.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.0
EPSS Ranking 5.8%