Important CVSS 9.1 EPSS 0.1035 2026-04 archive

Executive Summary

Improper verification of cryptographic signature in ASP.NET Core allows an unauthorized attacker to elevate privileges over a network.

Overview

9.1
CVSS CRITICAL
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
Category Elevation of Privilege
Released Apr 14 2026
Last Updated Apr 14 2026
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known
EPSS Score 0.1035 — 0.9513 percentile
NVD CVSS 9.1 CRITICAL — matches MSRC

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C
ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
None
USER INTERACTION
None
SCOPE
Unchanged
CONFIDENTIALITY
High
INTEGRITY
High
AVAILABILITY
None
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 7.9

EPSS Score

0.1035
probability of exploitation in the next 30 days
0.9513 percentile - updated 2026-06-21
View on FIRST.org

Affected Products

2 affected products
Product KB Article Severity Impact Restart Required
ASP.NET Core 10.0 5091596 (Security Update) Important Elevation of Privilege Maybe
Microsoft Visual Studio 2026 version 18.5 Release Notes (Security Update) Important Elevation of Privilege Maybe

Patches

2 patches
Article Type Restart
5091596 Security Update Maybe
Release Notes Security Update Maybe

Known Exploits

Acknowledgments

Anonymous