security/vuxml: Mark zeek < 5.0.9 as vulnerable as per:

https://github.com/zeek/zeek/releases/tag/v5.0.9

This release fixes the following potential DoS vulnerabilities:

• A specially-crafted series of FTP packets with a CMD command with a large path followed by a very large number of replies could cause Zeek to spend a long time processing the data.
• A specially-crafted with a truncated header can cause Zeek to overflow memory and potentially crash.
• A specially-crafted series of SMTP packets can cause Zeek to generate a very large number of events and take a long time to process them.
• A specially-crafted series of POP3 packets containing MIME data can cause Zeek to spend a long time dealing with each individual file ID.

Reported by: Tim Wojtulewicz