Computer Vision Annotation Tool (CVAT) is an interactive video and image annotation tool for computer vision. An attacker with an account on an affected CVAT instance is able to run arbitrary code in the context of the Nuclio function container. This vulnerability affects CVAT deployments that run any of the serverless functions of type tracker from the CVAT Git repository, namely TransT and SiamMask. Deployments with custom functions of type tracker may also be affected, depending on how they handle state serialization. If a function uses an unsafe serialization library such as pickle or jsonpickle, its likely to be vulnerable. Upgrade to CVAT 2.26.0 or later. If you are unable to upgrade, shut down any instances of the TransT or SiamMask functions youre running.
The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid.
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.