Important CVSS 4.2 EPSS 0.04326 2019-02 archive

Executive Summary

A vulnerability exists in Microsoft Chakra JIT server. An attacker who successfully exploited this vulnerability could gain elevated privileges. The vulnerability by itself does not allow arbitrary code to run. However, this vulnerability could be used in conjunction with one or more vulnerabilities (for example a remote code execution vulnerability and another elevation of privilege vulnerability) to take advantage of the elevated privileges when running. The security update addresses the vulnerability by modifying how Microsoft Chakra handles constructorCaches.

Overview

4.2
CVSS MEDIUM
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
Category Elevation of Privilege
Released Feb 12 2019
Last Updated Feb 12 2019
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known
EPSS Score 0.04326 — 0.89917 percentile

CVSS Vector

ATTACK VECTOR
Network
ATTACK COMPLEXITY
High
PRIVILEGES REQUIRED
None
USER INTERACTION
Required
SCOPE
Unchanged
Temporal Score: 3.8

EPSS Score

0.04326
probability of exploitation in the next 30 days
0.89917 percentile - updated 2026-06-20
View on FIRST.org

Affected Products

13 affected products
Product KB Article Severity Impact Restart Required
ChakraCore Release Notes (Security Update) Important Elevation of Privilege Maybe
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1703 for 32-bit Systems 4487020 (Security Update) Important Elevation of Privilege Yes
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1703 for x64-based Systems 4487020 (Security Update) Important Elevation of Privilege Yes
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1709 for 32-bit Systems 4486996 (Security Update) Important Elevation of Privilege Yes
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1709 for ARM64-based Systems 4486996 (Security Update) Important Elevation of Privilege Yes
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1709 for x64-based Systems 4486996 (Security Update) Important Elevation of Privilege Yes
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1803 for 32-bit Systems 4487017 (Security Update) Important Elevation of Privilege Yes
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1803 for ARM64-based Systems 4487017 (Security Update) Important Elevation of Privilege Yes
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1803 for x64-based Systems 4487017 (Security Update) Important Elevation of Privilege Yes
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1809 for 32-bit Systems 4487044 (Security Update) Important Elevation of Privilege Yes
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1809 for ARM64-based Systems 4487044 (Security Update) Important Elevation of Privilege Yes
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1809 for x64-based Systems 4487044 (Security Update) Important Elevation of Privilege Yes
Microsoft Edge (EdgeHTML-based) on Windows Server 2019 4487044 (Security Update) Low Elevation of Privilege Yes

Patches

5 patches
Article Type Restart
Release Notes Security Update Maybe
4487020 Security Update Yes
4486996 Security Update Yes
4487017 Security Update Yes
4487044 Security Update Yes

Known Exploits

Acknowledgments