CVE-2026-23737

Описание

seroval facilitates JS value stringification, including complex structures beyond JSON.stringify capabilities. In versions 1.4.0 and below, improper input handling in the JSON deserialization component can lead to arbitrary JavaScript code execution. Exploitation is possible via overriding constant value and error deserialization, allowing indirect access to unsafe JS evaluation. At minimum, attackers need the ability to perform 4 separate requests on the same function, and partial knowledge of how the serialized data is used during later runtime processing. This vulnerability affects the fromJSON and fromCrossJSON functions in a client-to-server transmission scenario. This issue has been fixed in version 1.4.0.

A flaw was found in seroval, a JavaScript library designed to convert complex data into a string format. This vulnerability exists within the library's JSON deserialization process, which is responsible for converting string data back into usable objects. A remote attacker can exploit improper input handling in the fromJSON and fromCrossJSON functions to execute arbitrary JavaScript code. Successful exploitation requires the attacker to make multiple specific requests and possess some understanding of how the serialized data is processed, ultimately leading to unauthorized control over the affected system.