Twisted is an event-based Python framework for internet applications. The Twisted Web HTTP 1.1 server parsed several HTTP request constructs more leniently than permitted by RFC 7230. This non-conformant parsing can lead to desync if requests pass through multiple HTTP parsers, potentially resulting in HTTP request smuggling.
For Debian 8 jessie, these problems have been fixed in version 14.0.2-3+deb8u5.
We recommend that you upgrade your twisted packages.
Further information about Extended LTS security advisories can be found at: https://deb.freexian.com/extended-lts/