Question: What is CVE-2025-1243?
Answer: CVE-2025-1243 is a vulnerability classified as low with a CVSS score of 2.0. It falls under CWE-311 and affects the system as follows: The Temporal api-go library prior to version 1.44.1 did not send `update response` information to Data Converter when the proxy package within the api-go module was used in a gRPC proxy prior to transmission. This resulted in information contained within the `update response` field not having Data Converter transformations (e.g. encryption) applied. This is an issue only when using the UpdateWorkflowExecution APIs (released on 13th January 2025)  with a proxy leveraging the api-go library before version 1.44.1.

Other data fields were correctly sent to Data Converter. This issue does not impact the Data Converter server. Data was encrypted in transit. Temporal Cloud services are not impacted.