tl/dr: Whether or not you have a reflected XSS vulnerability depends
on the exact method you use to append the data. Therefore you should
specifically check your chosen method to make sure it is safe. Modern
doesn't, so attention to detail is critical.
Your website may be vulnerable to a reflected XSS attack (It depends upon how you are setting that value and how the data is interpreted). For example, imagine if I access the following URL:
If your site converts this:
<a href="secondurl.com">Link </a>
I would suggest rethinking your approach.
Hashes are not virus signatures; they only serve as a fingerprint to identify files. With most conventional hash algorithms (e.g. SHA256), modifying the input slightly results in an entirely different hash output. Thus there is no correlation between malicious features in your virus files and their hashes. ...
There's nothing wrong with your code there. What you're getting is a code compile error, and your code is syntactically fine.
I'm running your code just dumping the variables rather than trying to send an email:
$to = 'email@example.com';
$subject = 'the subject';
$message = 'hello';
$headers = 'From: firstname.lastname@example.org' . "\r\n";
I posted about it on the python bug tracker and got some advice.
Since python interprets files line-by-line, we can delay the termination error, which leads to this interesting bug, simply by adding a new line \n to leak a line at a time.
The proof of concept is as follows:
Create target File
$ cat /tmp/passwd
Read from ...
One of the requirements of Pypi is that the URI contains "api/pypi" on the path, so with a good firewall you can put a rule that only allows your domain that you trust pip and you can reject the rest with a regular expression that contains the api/pypi.
Is it a good counter-measure for this kind of a situation?
No. Unfortunately what you're planning to do won't address this specific threat. Here, the attackers compromised the package on PyPI itself, hence it was downloaded from the original source, so limiting downloads only to PyPI would have no effect.
In most cases, these compromised packages come in ...