Critical CVSS 9.8 EPSS 0.0084 2026-04 archive

Executive Summary

Deserialization of untrusted data in Microsoft Bing allows an unauthorized attacker to execute code over a network.

Overview

9.8
CVSS CRITICAL
Critical
MS Severity
Not Exploited
MS Exploit Status
N/A
MS Exploit Likelihood
Category Remote Code Execution
Released Apr 14 2026
Last Updated Apr 14 2026
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known
EPSS Score 0.0084 — 0.53021 percentile
NVD CVSS 9.8 CRITICAL — differs from MSRC

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/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
High
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 8.7

EPSS Score

0.0084
probability of exploitation in the next 30 days
0.53021 percentile - updated 2026-06-21
View on FIRST.org

Known Exploits

Acknowledgments

Microsoft has not published researcher acknowledgments for this CVE, or they are not yet reflected in our data source. Check the MSRC advisory directly for the most current credit information.