A deserialization of untrusted data vulnerability was found in ManageIQ. The YamlLoadAliases module overrides YAML.safeload to silently fall back to YAML.unsafeload in production when a Psych::DisallowedClass error occurs. An authenticated attacker with dialog import access can exploit this to achieve remote code execution by uploading a crafted YAML payload that triggers the fallback and deserializes arbitrary Ruby objects.

Red Hat CloudForms, which was based on ManageIQ, has reached End of Life and is no longer supported. No errata or patches will be issued. This CVE is being assigned for the benefit of the ManageIQ community and downstream consumers.

A deserialization vulnerability was found in ManageIQ. The YamlLoadAliases module in lib/extensions/yamlloadaliases.rb overrides YAML.safeload globally. When a Psych::DisallowedClass error is raised in production, instead of raising the error, it silently falls back to YAML.unsafeload, which deserializes arbitrary Ruby objects. An authenticated user with dialog import access can upload a crafted YAML payload containing classes outside the permitted list to trigger the fallback and achieve Remote Code Execution via standard Ruby gadget chains.

The code comment explicitly labels this a "Temporary hack to fallback to psych 3 behavior" but it was never removed.