Files @ aa51aca7fd1a
Branch filter:

Location: kallithea/MIT-Permissive-License.txt

Valentin Kleibel
controller: Handle UnicodeDecodeError from webob decoding invalid URLs

webob will try to utf-8 decode all %-encoded bytes in URL-parameters, but will
not handle Unicode erors ... and neither did Kallithea. Visiting a URL like
http://localhost:5000/?%AD would thus give an unhandled exception showing
"Internal Server Error" to the user, and logging the full traceback and:

WebApp Error: UnicodeDecodeError: 'utf-8' codec can't decode byte 0xad in position 0: invalid start byte

This has been seen a lot recently from attackers probing for a php
vulnerability
https://devco.re/blog/2024/06/06/security-alert-cve-2024-4577-php-cgi-argument-injection-vulnerability-en/ .

Now handle these exceptions more nicely and reject with "400 Bad Request".
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.