Server monitoring applications, by their nature, have to interact with the system by issuing the commands that will collect data. The most common solution is to separate the application in to two parts:
Back-end: a daemon process that runs at an interval, collecting data and writing it to a data store.
Front-end: connects to the data store, processes statistics, and formats for display.
By constructing your application in this way, the data store acts as a firewall between the system calls required to collect the data and the interface used to view the data. Your daemon application needn't listen on any network ports if it is running locally.
Your web application still needs to be secure, but you don't have the additional risk of many calls to system/shell exec commands that are a honey pot for exploitation.
In anything that is not PHP. Bash would have been perfect for this use case, for example. The correct way to do this is to obtain the data separately and merely show it on the interface. I haven't audited the code, so I don't know what's being passed to the shell commands, but the fact that an attacker MIGHT be able to influence the commands being executed (see register_globals, etc (yes, I know this has been disabled by default in recent versions of PHP)) is enough for me to completely write it off as an unnecesary risk.
By collecting the data periodically (i.e a cron job) you eliminate most possible vulnerabilities.
First you say anything not PHP then you don't mention one. While I agree that off-request collection may be wiser, I fail to see anything mentioned better than PHP unless you're seriously mentioning Bash to write a webapp like this. Mentioning an old security concern that is no longer an issue seems like an easy way to discount every possible language.
I said that a bash script would be perfect for collecting data periodically and saving it to a file, I wasn't suggesting that you use it to write a web app. I thought that was clear; apologies if it wasn't.
However, you say that this is an easy way to discount every possible language: can you point me to a vulnerability on the same level as register_globals in any other language?
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Some server side code is required to obtain the data. Out of curiosity, what would it have to be written in to make you feel safe?
Server monitoring applications, by their nature, have to interact with the system by issuing the commands that will collect data. The most common solution is to separate the application in to two parts:
Back-end: a daemon process that runs at an interval, collecting data and writing it to a data store.
Front-end: connects to the data store, processes statistics, and formats for display.
By constructing your application in this way, the data store acts as a firewall between the system calls required to collect the data and the interface used to view the data. Your daemon application needn't listen on any network ports if it is running locally.
Your web application still needs to be secure, but you don't have the additional risk of many calls to system/shell exec commands that are a honey pot for exploitation.
In anything that is not PHP. Bash would have been perfect for this use case, for example. The correct way to do this is to obtain the data separately and merely show it on the interface. I haven't audited the code, so I don't know what's being passed to the shell commands, but the fact that an attacker MIGHT be able to influence the commands being executed (see register_globals, etc (yes, I know this has been disabled by default in recent versions of PHP)) is enough for me to completely write it off as an unnecesary risk.
By collecting the data periodically (i.e a cron job) you eliminate most possible vulnerabilities.
First you say anything not PHP then you don't mention one. While I agree that off-request collection may be wiser, I fail to see anything mentioned better than PHP unless you're seriously mentioning Bash to write a webapp like this. Mentioning an old security concern that is no longer an issue seems like an easy way to discount every possible language.
I said that a bash script would be perfect for collecting data periodically and saving it to a file, I wasn't suggesting that you use it to write a web app. I thought that was clear; apologies if it wasn't.
However, you say that this is an easy way to discount every possible language: can you point me to a vulnerability on the same level as register_globals in any other language?