Important CVSS 6.5 EPSS 0.24172 ⚠️ Exploited in the wild 2026-04 archive

Executive Summary

Improper input validation in Microsoft Office SharePoint allows an unauthorized attacker to perform spoofing over a network.

Overview

6.5
CVSS MEDIUM
Important
MS Severity
Exploited
MS Exploit Status
Exploitation Detected
MS Exploit Likelihood
Category Spoofing
Released Apr 14 2026
Last Updated Apr 14 2026
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known
EPSS Score 0.24172 — 0.97568 percentile
NVD CVSS 6.5 MEDIUM — matches MSRC

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:F/RL:O/RC:C
ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
None
USER INTERACTION
None
SCOPE
Unchanged
CONFIDENTIALITY
Low
INTEGRITY
Low
AVAILABILITY
None
EXPLOIT CODE MATURITY
Functional
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 6.0

EPSS Score

0.24172
probability of exploitation in the next 30 days
0.97568 percentile - updated 2026-06-21
View on FIRST.org

Affected Products

3 affected products
Product KB Article Severity Impact Restart Required
Microsoft SharePoint Enterprise Server 2016 5002861 (Security Update) Important Spoofing Maybe
Microsoft SharePoint Server 2019 5002854 (Security Update) Important Spoofing Maybe
Microsoft SharePoint Server Subscription Edition 5002853 (Security Update) Important Spoofing Maybe

Patches

3 patches
Article Type Restart
5002861 Security Update Maybe
5002854 Security Update Maybe
5002853 Security Update Maybe

Known Exploits

Acknowledgments

Microsoft