opensearch-ruby is a community-driven, open source fork of elasticsearch-ruby. In versions prior to 2.0.1 the ruby YAML.load function was used instead of YAML.safe_load. As a result opensearch-ruby 2.0.0 and prior can lead to unsafe deserialization using YAML.load if the response is of type YAML. An attacker must be in control of an opensearch server and convince the victim to connect to it in order to exploit this vulnerability. The problem has been patched in opensearch-ruby gem version 2.0.1. Users are advised to upgrade. There are no known workarounds for this issue.
The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Opensearch | Amazon | * | 2.0.2 (excluding) |
It is often convenient to serialize objects for communication or to save them for later use. However, deserialized data or code can often be modified without using the provided accessor functions if it does not use cryptography to protect itself. Furthermore, any cryptography would still be client-side security – which is a dangerous security assumption. Data that is untrusted can not be trusted to be well-formed. When developers place no restrictions on “gadget chains,” or series of instances and method invocations that can self-execute during the deserialization process (i.e., before the object is returned to the caller), it is sometimes possible for attackers to leverage them to perform unauthorized actions, like generating a shell.