CVE-2026-47631

HighUpdated

Published: 09 June 2026

Published

09 June 2026

Modified

17 June 2026

KEV Added

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Patch

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CVSS Score v3.1 8.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

EPSS Score 0.0035 27.3th percentile

Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-47631 is a high-severity Cross-site Scripting (CWE-79) vulnerability in Microsoft Exchange Server. Its CVSS base score is 8.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 27.3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

🇪🇺 ENISA EUVD: EUVD-2026-35506

Vulnerability details

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.

CWE(s): CWE-79

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

attack.mitre.org →

T1185 Browser Session Hijacking Collection

Adversaries may take advantage of security vulnerabilities and inherent functionality in browser software to change content, modify user-behaviors, and intercept information as part of various browser session hijacking techniques.

attack.mitre.org →

T1539 Steal Web Session Cookie Credential Access

An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.

attack.mitre.org →

Why these techniques?

XSS (CWE-79) in public-facing Exchange Server web interface directly enables exploitation of the server (T1190) and facilitates browser session hijacking or cookie theft via injected scripts (T1185, T1539).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0