Path traversal when MessageBus::Diagnostics is enabled
GHSA-xmgj-5fh3-xjmm · CVE-2021-43840
Published · Modified
AI SAST
Find this class of vulnerability in your own code
Corgea's AI-native static analysis detects vulnerabilities like this one across your repositories, ranks them by exploitability, and returns review-ready fixes.
Description
Impact
Users who deployed message bus with diagnostics features enabled (default off) were vulnerable to a path traversal bug, which could lead to disclosure of secret information on a machine if an unintended user were to gain access to the diagnostic route. The impact is also greater if there is no proxy for your web application as the number of steps up the directories is not bounded. For deployments which uses a proxy, the impact varies. For example, If a request goes through a proxy like Nginx with merge_slashes enabled, the number of steps up the directories that can be read is limited to 3 levels.
Patches
Patched in 3.3.7.
Workarounds
Disable MessageBus::Diagnostics in production like environments.
References
- WEB https://github.com/discourse/message_bus/security/advisories/GHSA-xmgj-5fh3-xjmm
- ADVISORY https://nvd.nist.gov/vuln/detail/CVE-2021-43840
- WEB https://github.com/discourse/message_bus/commit/9b6deee01ed474c7e9b5ff65a06bb0447b4db2ba
- PACKAGE https://github.com/discourse/message_bus
- WEB https://github.com/rubysec/ruby-advisory-db/blob/master/gems/message_bus/CVE-2021-43840.yml
Ready to move
Start Securing
Free, no credit card | First findings in minutes