CVE-2026-20824 is a security feature bypass vulnerability affecting Windows’ Remote Assistance / Quick Assist feature. It was publicly disclosed on January 13, 2026 as part of Microsoft’s January Patch Tuesday security updates.
What It Is
- Type: Protection mechanism failure (security feature bypass)
- Component: Windows Remote Assistance (part of Windows support/remote help tools)
- Impact: Attackers can bypass built-in security checks (like Mark of the Web defenses) that normally protect users from untrusted content.
- Severity: Rated Important by Microsoft.
Technical Details
- CVSS v3.1 base score: 5.5 (Moderate)
- Attack Vector: Local (requires attacker to have access to the system)
- Privileges Required: None
- User Interaction: Required (victim must open a crafted file)
- Confidentiality Impact: High (attacker may access sensitive data)
- Integrity & Availability Impact: None/Not directly affected in typical exploit scenarios.
The flaw stems from how Windows Remote Assistance processes certain files or content, allowing attackers to evade the usual protections enforced on files from untrusted sources (like internet downloads).
Exploitation Conditions & Risk
- Local access needed: An attacker must already have some level of access to the affected system.
- User must interact: The victim must open a specially crafted file (e.g., delivered via email or malicious website).
- No public widespread exploitation reported yet: Microsoft assesses exploitation as less likely at this time.
Mitigation & Patch
Microsoft has released security updates for this issue in the January 2026 Patch Tuesday updates — administrators and users should install the latest Windows cumulative updates to remediate the flaw.
