CVE-2021-43807
HTTP Method Spoofing
描述
Opencast versions prior to 9.10 allow HTTP method spoofing, allowing to change the assumed HTTP method via URL parameter. This allows attackers to turn HTTP GET requests into PUT requests or an HTTP form to send DELETE requests. This bypasses restrictions otherwise put on these types of requests and aids in cross-site request forgery (CSRF) attacks, which would otherwise not be possible. ### Impact The vulnerability allows attackers to craft links or forms which may change the server state. For example, the following GET request would create a new user: ```sh % curl -i -u admin:opencast \ 'https://legacy.opencast.org/admin-ng/users/test.json?_method=PUT&username=test&password=attack' HTTP/2 200 … ``` If an admin is logged in to legacy.opencast.org and accidentally clicks this link, a user will silently be created. ### Patches This issue is fixed in Opencast 9.10 and 10.0. ### Workarounds You can mitigate the problem by setting the `SameSite=Strict` attribute for your cookies. If this is a viable option for you depends on your integrations. We strongly recommend updating in any case. ### References - [Fix for 10.0](https://github.com/opencast/opencast/commit/59cb6731067283e54f15462be38b6117d8b9ea8b#diff-9c5fb3d1b7e3b0f54bc5c4182965c4fe1f9023d449017cece3005d3f90e8e4d8) - [Fix for 9.10](https://github.com/opencast/opencast/commit/8f8271e1085f6f8e306c689d6a56b0bb8d076444) ### For more information If you have any questions or comments about this advisory: * Open an issue in [our issue tracker](https://github.com/opencast/opencast/issues) * Email us at [security@opencast.org](mailto:security@opencast.org)
如何修補 CVE-2021-43807
要修補 CVE-2021-43807,請將受影響套件升級到下列已修補版本。
- —升級至 9.10 或更新版本
CVE-2021-43807 正在被利用嗎?
低 — EPSS 為 1.4%,目前沒有觀察到大規模利用活動。
受影響套件(1)
- from 0, < 9.10