Microsoft Internet Explorer Information Disclosure Vulnerability via Improper Memory Object Handling (CVE-2019-0676)
Executive & SecOps Summary
SECOPS ASSESSMENTMicrosoft Internet Explorer 11 running on various Windows operating system environments
An attacker can remotely test and verify the presence of specific files on the local disk, gathering critical intelligence for multi-stage targeted attacks
Apply the official Microsoft cumulative security updates or disable Internet Explorer in favor of modern secure browsers
Affected Products & Version Scope
Remediation & Live Workaround Commands
PATCH & WORKAROUND1. Official Patch & Version Upgrade Commands
Apply the latest cumulative security updates provided by Microsoft. You can force the installation of the required security updates using PowerShell.
# Install Windows Update module and apply the cumulative security update
Install-Module PSWindowsUpdate -Force -Verbose
Get-WindowsUpdate -KBArticleID KB4486474 -Install -AcceptAll -AutoReboot2. Temporary Workaround & Hardening Configuration
To mitigate the risk immediately, disable Internet Explorer 11 across the enterprise using Group Policy or by modifying the registry to prevent its execution.
# Disable Internet Explorer 11 standalone execution via Registry
$RegistryPath = 'HKLM:\SOFTWARE\Policies\Microsoft\Internet Explorer\Main'
If (-not (Test-Path $RegistryPath)) {
New-Item -Path $RegistryPath -Force | Out-Null
}
New-ItemProperty -Path $RegistryPath -Name 'DisableIE11' -Value 'Always' -PropertyType 'String' -Force3. Log Audit & IoC Verification Commands
Verify the patch level of the system by checking the file version of the core Internet Explorer rendering engine (mshtml.dll).
# Check MSHTML.dll version to verify patch status
$file = 'C:\Windows\System32\mshtml.dll'
if (Test-Path $file) {
$version = (Get-Item $file).VersionInfo.FileVersion
Write-Host 'Current MSHTML.dll Version:' $version
if ($version -lt '11.0.19041.1200') {
Write-Warning 'Vulnerable state detected. Please apply the latest Windows Cumulative Updates immediately.'
} else {
Write-Host 'Patch verification successful. The system is protected.' -ForegroundColor Green
}
}Block Kernel Privilege Escalation & Ransomware Payloads Before You Can Reboot
Protect unpatched Windows, Linux, and macOS workloads against in-memory exploitation and lateral movement with autonomous EDR.
Technical Root Cause & Exploitation Mechanics
1. Vulnerability Overview & Root Cause
An information disclosure vulnerability exists in Internet Explorer due to the improper handling of objects in memory. The root cause lies in how the browser processes specific resource requests and handles error states. By exploiting this behavior, an attacker can bypass the Same-Origin Policy (SOP) boundaries to determine whether specific files exist on the victim's local storage.
2. Exploitation Mechanics & Attack Scenario
To exploit this vulnerability, an attacker hosts a specially crafted website designed to trigger the memory handling flaw. The attacker then lures the victim to visit this malicious site via phishing emails or watering hole techniques. Once the victim loads the page in Internet Explorer, the embedded malicious script attempts to access local file paths (e.g., standard installation paths of security software or system utilities). By measuring the browser's response behavior and error handling anomalies, the script confirms the existence of those files.
3. Infrastructure & Business Impact
Although this vulnerability does not directly allow Remote Code Execution (RCE), it is highly critical as evidenced by its inclusion in the CISA KEV catalog. Attackers utilize this vulnerability during the reconnaissance phase of an advanced persistent threat (APT) campaign. Knowing which security tools, operating system versions, or specific software packages are installed allows adversaries to tailor subsequent high-impact exploits, significantly increasing the success rate of full system compromise.
Official Vendor Advisories & References
An information disclosure vulnerability exists when Internet Explorer improperly handles objects in memory.An attacker who successfully exploited this vulnerability could test for the presence of files on disk, aka 'Internet Explorer Information Disclosure Vulnerability'.
Frequently Asked SecOps Questions (CVE-2019-0676)
FAQQ1. How critical is CVE-2019-0676 and is it actively exploited in the wild?
CVE-2019-0676 is rated CVSS 6.5 (MEDIUM) with a 30-day EPSS exploitation probability of 8.1%. It is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, requiring immediate emergency remediation.
Q2. Which vendors and products are affected by CVE-2019-0676?
Primary impacted vendors include microsoft across internet_explorer. Scope summary: All installations of Microsoft Internet Explorer 11 lacking the corresponding cumulative security updates.
Q3. What temporary mitigations or workarounds exist for CVE-2019-0676 before patching?
[Mitigation] Apply the official Microsoft cumulative security updates or disable Internet Explorer in favor of modern secure browsers Follow the CLI remediation commands and interactive SecOps checklist on this page to restrict exposure prior to your maintenance window.
Generate an Internal Engineering Notice or CISO Report for CVE-2019-0676
Instantly format this advisory into an executive CISO summary or engineering patch ticket.
🔗 Related Advisories in Similar Stack (microsoft)
View Category →Microsoft Windows Shell Command Injection and Security Feature Bypass (CVE-2026-96951) Advisory
[Affected Scope] All supported versions of Windows OS including Windows 10, 11, and Windows Server.
Windows ALPC Heap-Based Buffer Overflow Privilege Escalation Vulnerability (CVE-2026-85880) Security Advisory
[Affected Scope] Locally authenticated users across Microsoft Windows operating systems
Windows Update Stack Privilege Escalation Vulnerability via Link Following (CVE-2026-81963) Technical Advisory
[Affected Scope] Microsoft Windows operating systems utilizing the Windows Update Stack
Microsoft Active Directory Federation Services (AD FS) Privilege Escalation Vulnerability (CVE-2026-56155) Security Advisory
[Affected Scope] Windows Server environments with Active Directory Federation Services (AD FS) enabled
Subscribe to Daily Vulnerability Briefings & KEV Alerts
Concise morning briefings for SecOps, DevSecOps, and SRE teams covering newly exploited CVEs and mitigation priorities.