{"id":"GHSA-7r9x-qrpr-3cxw","summary":"mofh Vulnerable to Improper Restriction of XML External Entity Reference","details":"The `xml.etree.ElementTree` module that mofh used up until version `1.0.1` implements a simple and efficient API for parsing and creating XML data. But it makes the application vulnerable to:\n\n- [Billion Laughs attack](https://en.wikipedia.org/wiki/Billion_laughs_attack): It is a type of denial-of-service attack aimed at XML parsers. It uses multiple levels of nested entities. If one large entity is repeated with a couple of thousand chars repeatedly, the parser gets overwhelmed.  \n- [Quadratic blowup attack](https://www.acunetix.com/vulnerabilities/web/xml-quadratic-blowup-denial-of-service-attack/): It is similar to a Billion Laughs attack. It abuses entity expansion, too. Instead of nested entities, it repeats one large entity with a couple of thousand chars repeatedly.\n\nThe Problem has been patched starting from version `1.0.1` by utilising the `defusedxml` package instead of `xml.etree.ElementTree`.\n\n### Workarounds\nFor this vulnerability to be exploited the user must be using a custom API URL, which has to be manually given using the `api_url` argument, or MyOwnFreeHost's API must be hacked. So, if the user did not use a custom API URL they _should_ be fine, however, upgrading is still advised.\n\nAnother workaround could be to call `defusedxml.defuse_stdlib()` before making any requests using the client.","modified":"2024-12-03T06:07:30.576416Z","published":"2022-08-11T18:06:05Z","database_specific":{"github_reviewed":true,"github_reviewed_at":"2022-08-11T18:06:05Z","nvd_published_at":null,"cwe_ids":["CWE-611"],"severity":"MODERATE"},"references":[{"type":"WEB","url":"https://github.com/Wallvon/mofh/security/advisories/GHSA-7r9x-qrpr-3cxw"},{"type":"WEB","url":"https://github.com/Wallvon/mofh/commit/da0d33cfd368e2f237ab28bf7a7f00e3d281005a"},{"type":"PACKAGE","url":"https://github.com/Wallvon/mofh"},{"type":"WEB","url":"https://www.acunetix.com/vulnerabilities/web/xml-quadratic-blowup-denial-of-service-attack"}],"affected":[{"package":{"name":"mofh","ecosystem":"PyPI","purl":"pkg:pypi/mofh"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.0.1"}]}],"versions":["0.0.1","0.0.2","0.0.3","0.0.4","1.0.0"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2022/08/GHSA-7r9x-qrpr-3cxw/GHSA-7r9x-qrpr-3cxw.json"}}],"schema_version":"1.9.0"}