CVE-2021-43840

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Summary

CVECVE-2021-43840
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-12-17 19:15:00 UTC
Updated2021-12-29 18:39:00 UTC
Descriptionmessage_bus is a messaging bus for Ruby processes and web clients. In versions prior to 3.3.7 users who deployed message bus with diagnostics features enabled (default off) are 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. This issue has been patched in version 3.3.7. Users unable to upgrade should ensure that MessageBus::Diagnostics is disabled.

Risk And Classification

Problem Types: CWE-22

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Discourse Message Bus All All All All

References

ReferenceSourceLinkTags
SECURITY: Fix path traversal on diagnostics route. · discourse/message_bus@9b6deee · GitHub MISC github.com
Path traversal when MessageBus::Diagnostics is enabled · Advisory · discourse/message_bus · GitHub CONFIRM github.com
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