A flaw was found in the way mailx handled the parsing of email addresses. A syntactically valid email address could allow a local attacker to cause mailx to execute arbitrary shell commands through shell meta-characters and the direct command execution functionality. Note: Applications using mailx to send email to addresses obtained from untrusted sources will still remain vulnerable to other attacks if they accept email addresses which start with "-" . To counteract this issue, this update also introduces the "--" option, which will treat the remaining command line arguments as email addresses.