CVE-2026-7191- Arbitrary Code Execution via Sandbox Bypass in QnABot on AWS

Bulletin ID: 2026-020-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 2026/04/27 13:15 PM PDT Description: QnABot on AWS is an open-source solution that provides a multi-channel, multi-language conversational interface powered by Amazon Lex, Amazon OpenSearch Service, and optionally Amazon Bedrock. We identified CVE-2026-7191, where the improper use of the static-eval npm package may allow an authenticated administrator to execute arbitrary code within the fulfillment Lambda execution context. By injecting a crafted conditional chaining expression via the Content Designer interface, an actor with Admin access could bypass the intended expression sandbox through JavaScript prototype manipulation. Successful exploitation may grant direct access to backend resources, including Lambda environment variables, OpenSearch indices, S3 objects, and DynamoDB tables, that are not exposed through normal administrative interfaces. Impacted versions: Please refer to the article below for the most up-to-date and complete information related to this AWS Security Bulletin.