Important CVSS 5.3 EPSS 0.00836 2025-12 archive

Executive Summary

User interface (ui) misrepresentation of critical information in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.

Overview

5.3
CVSS MEDIUM
Important
MS Severity
Not Exploited
MS Exploit Status
Exploitation Unlikely
MS Exploit Likelihood
Category Spoofing
Released Dec 9 2025
Last Updated Dec 9 2025
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known
EPSS Score 0.00836 — 0.53988 percentile
NVD CVSS 5.3 MEDIUM — matches MSRC

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:U/RL:O/RC:C
ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
None
USER INTERACTION
None
SCOPE
Unchanged
CONFIDENTIALITY
None
INTEGRITY
Low
AVAILABILITY
None
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 4.6

EPSS Score

0.00836
probability of exploitation in the next 30 days
0.53988 percentile - updated 2026-07-25
View on FIRST.org

Affected Products

4 affected products
Product KB Article Severity Impact Restart Required
Microsoft Exchange Server 2016 Cumulative Update 23 5071873 (Security Update) Important Spoofing Yes
Microsoft Exchange Server 2019 Cumulative Update 14 5071874 (Security Update) Important Spoofing Yes
Microsoft Exchange Server 2019 Cumulative Update 15 5071875 (Security Update) Important Spoofing Yes
Microsoft Exchange Server Subscription Edition RTM 5071876 (Security Update) Important Spoofing Yes

Patches

4 patches
Article Type Restart
5071873 Security Update Yes
5071874 Security Update Yes
5071875 Security Update Yes
5071876 Security Update Yes

Known Exploits

Acknowledgments

Tushar Maroo with Microsoft