Published: 19 June 2017
Exim supports the use of multiple "-p" command line arguments which are malloc()'ed and never free()'ed, used in conjunction with other issues allows attackers to cause arbitrary code execution. This affects exim version 4.89 and earlier. Please note that at this time upstream has released a patch (commit 65e061b76867a9ea7aeeb535341b790b90ae6c21), but it is not known if a new point release is available that addresses this issue at this time.
From the Ubuntu security team
It was discovered that Exim did not properly deallocate memory when processing certain command line arguments. A local attacker could use this in conjunction with another vulnerability to possibly execute arbitrary code and gain administrative privileges.
CVSS 3 base score: 4.0