Описание
Feedgen Vulnerable to XML Denial of Service Attacks
Impact
The feedgen library allows supplying XML as content for some of the available fields. This XML will be parsed and integrated into the existing XML tree. During this process, feedgen is vulnerable to XML Denial of Service Attacks (e.g. XML Bomb).
This becomes a concern in particular if feedgen is used to include content from untrused sources and if XML (including XHTML) is directly included instead of providing plain tex content only.
Patches
This problem has been fixed in feedgen 0.9.0 which disallows XML entity expansion and external resources.
Workarounds
Updating is strongly recommended and should not be problematic. Nevertheless, as a workaround, avoid providing XML directly to feedgen or ensure that no entity expansion is part of the XML.
References
For more information
If you have any questions or comments about this advisory:
- Open an issue in lkiesow/python-feedgen
- Send an email to security@lkiesow.de
Ссылки
- https://github.com/lkiesow/python-feedgen/security/advisories/GHSA-g8q7-xv52-hf9f
- https://nvd.nist.gov/vuln/detail/CVE-2020-5227
- https://github.com/lkiesow/python-feedgen/commit/f57a01b20fa4aaaeccfa417f28e66b4084b9d0cf
- https://docs.microsoft.com/en-us/archive/msdn-magazine/2009/november/xml-denial-of-service-attacks-and-defenses
- https://github.com/pypa/advisory-database/tree/main/vulns/feedgen/PYSEC-2020-231.yaml
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/T6I5ENUYGFNMIH6ZQ62FZ6VU2WD3SIOI
Пакеты
feedgen
< 0.9.0
0.9.0
Связанные уязвимости
Feedgen (python feedgen) before 0.9.0 is susceptible to XML Denial of Service attacks. The *feedgen* library allows supplying XML as content for some of the available fields. This XML will be parsed and integrated into the existing XML tree. During this process, feedgen is vulnerable to XML Denial of Service Attacks (e.g. XML Bomb). This becomes a concern in particular if feedgen is used to include content from untrused sources and if XML (including XHTML) is directly included instead of providing plain tex content only. This problem has been fixed in feedgen 0.9.0 which disallows XML entity expansion and external resources.