By The Hacker News
Publication Date: 2026-05-15 06:19:00
Microsoft has disclosed a new security vulnerability impacting on-premise versions of Exchange Server that it said has come under active exploitation in the wild.
The vulnerability, tracked as CVE-2026-42897 (CVSS score: 8.1), has been described as a spoofing bug stemming from a cross-site scripting flaw. An anonymous researcher has been credited with discovering and reporting the issue.
“Improper neutralization of input during web page generation (‘cross-site scripting’) in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network,” the tech giant said in a Thursday advisory.
Microsoft, which tagged the vulnerability with an “Exploitation Detected” assessment, said an attacker could weaponize it by sending a crafted email to a user, which, when opened in Outlook Web Access and subject to other “certain interaction conditions,” can allow arbitrary JavaScript code to be executed in the…
