GHSA-xmgj-5fh3-xjmm
Path traversal when MessageBus::Diagnostics is enabled
Quick fix
GHSA-xmgj-5fh3-xjmm — message_bus: upgrade to the fixed version with the command below.
bundle update message_busDetails
### 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.
Are you affected?
Enter the version of the package you're using.
Affected packages
References
- https://github.com/discourse/message_bus/security/advisories/GHSA-xmgj-5fh3-xjmm[WEB]
- https://nvd.nist.gov/vuln/detail/CVE-2021-43840[ADVISORY]
- https://github.com/discourse/message_bus/commit/9b6deee01ed474c7e9b5ff65a06bb0447b4db2ba[WEB]
- https://github.com/discourse/message_bus[PACKAGE]
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/message_bus/CVE-2021-43840.yml[WEB]