Microsoft Security Response Center guidance
Vendor revision: Oct 29, 2026Release Notes
Vulnerability intelligence
CVE-2026-115897 and is rated Low severity with a CVSS score of 2.1. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
Release Notes
Serialize JavaScript serializes JavaScript values to a superset of JSON that includes regular expressions and functions. Prior to 7.1.3, the function-source escaping logic does not neutralize a bare closing-script prefix when attacker-influenced function source text ends exactly at that prefix.
Because each function body is escaped independently, a delimiter supplied by surrounding serialized output can terminate an HTML script element, and a later serialized value supplies injected markup that becomes a live element in the page. Exploitation requires control of a serialized function's source text, such as through a spoofed toString().
This issue is fixed in version 7.1.3.
Source: NVD