OnlyFm252
Microsoft Exchange Server

CVE-2026-45501 — Microsoft Exchange Server Spoofing Vulnerability

Important CVSS 6.1 EPSS 0.00297 2026-06 archive

Executive Summary

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.

Overview

6.1
CVSS MEDIUM
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
Category Spoofing
Released Jun 9 2026
Last Updated Jun 9 2026
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known
EPSS Score 0.00297 — 0.21105 percentile
NVD CVSS 6.1 MEDIUM — differs from MSRC

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C
ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
None
USER INTERACTION
Required
SCOPE
Changed
CONFIDENTIALITY
High
INTEGRITY
None
AVAILABILITY
None
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 5.7

EPSS Score

0.00297
probability of exploitation in the next 30 days
0.21105 percentile - updated 2026-06-21
View on FIRST.org

Affected Products

4 affected products
Product KB Article Severity Impact Restart Required
Microsoft Exchange Server 2016 Cumulative Update 23 5094144 (Security Update) Important Spoofing Yes
Microsoft Exchange Server 2019 Cumulative Update 14 5094142 (Security Update) Important Spoofing Yes
Microsoft Exchange Server 2019 Cumulative Update 15 5094140 (Security Update) Important Spoofing Yes
Microsoft Exchange Server Subscription Edition RTM 5094139 (Security Update) Important Spoofing Yes

Patches

4 patches
Article Type Restart
5094144 Security Update Yes
5094142 Security Update Yes
5094140 Security Update Yes
5094139 Security Update Yes

Known Exploits

Acknowledgments

MARIOS GYFTOS, DongJun Kim (smlijun), Hwiwon Lee (hwiwonl) with UIUC, Jongseong Kim (nevul37) with UIUC, TALHA GÜNAY, Younggi Park (grill66) with UIUC, Artemy Tsetsersky

On This Page