Security News Windows Remote Assistance Vulnerability Allow Attacker to Bypass Security Features

[Brownie2019]

Content source

https://cybersecuritynews.com/windows-remote-assistance-vulnerability/

Critical security updates addressing CVE-2026-20824, a protection mechanism failure in Windows Remote Assistance that permits attackers to circumvent the Mark of the Web (MOTW) defense system.
The vulnerability was disclosed on January 13, 2026, and affects multiple Windows platforms spanning from Windows 10 through Windows Server 2025.
CVE-2026-20824 represents a security feature bypass vulnerability with an Important severity rating.
The flaw enables unauthorized local attackers to evade MOTW defenses, a built-in protection mechanism designed to restrict dangerous actions on files downloaded from untrusted sources.

Read more:

Windows Remote Assistance Vulnerability Allow Attacker to Bypass Security Features

Microsoft released critical updates to fix a Windows Remote Assistance flaw that lets attackers bypass Mark of the Web protections.

cybersecuritynews.com

 

[Bot]

Read more:

Windows Remote Assistance Vulnerability Allow Attacker to Bypass Security Features

Microsoft released critical updates to fix a Windows Remote Assistance flaw that lets attackers bypass Mark of the Web protections.

cybersecuritynews.com

The quoted write-up matches the high-level classification (Windows Remote Assistance, “protection mechanism failure”, local security feature bypass), but I would be cautious about treating the “Mark of the Web (MOTW) bypass” part as confirmed.

From the public CVE records, CVE-2026-20824 is described generically as a protection mechanism failure in Windows Remote Assistance that “allows an unauthorized attacker to bypass a security feature locally.” It’s scored CVSS 3.1 5.5 (AV:L / UI:R) and is not described as a remote/unauthenticated Internet attack. ([nvd.nist.gov](https://nvd.nist.gov/vuln/detail/CVE-2026-20824?utm_source=openai))

What this likely means in practical terms

• This is primarily relevant if an attacker can already execute code locally (or can get a user to open/launch something locally), since it is a local attack scenario (AV:L). ([nvd.nist.gov](https://nvd.nist.gov/vuln/detail/CVE-2026-20824?utm_source=openai))
• Because it’s a “security feature bypass”, the usual risk is that it can help an attacker get around a Windows safeguard (for example, protections applied to untrusted content). However, the official public description available via NVD does not explicitly mention MOTW, so I would not treat “MOTW bypass” as definitive unless Microsoft publishes that detail in an advisory/FAQ. ([nvd.nist.gov](https://nvd.nist.gov/vuln/detail/CVE-2026-20824?utm_source=openai))

What to do (safe, standard guidance)

• Apply the January 2026 Windows security updates on affected endpoints/servers as part of normal patching. (Microsoft is the CNA for this CVE and a vendor fix is available as of the 2026-01-13 publication date.) ([nvd.nist.gov](https://nvd.nist.gov/vuln/detail/CVE-2026-20824?utm_source=openai))
• If your environment does not need Windows Remote Assistance, disable it / block it via policy. This reduces exposure even for “local + user interaction” issues.
• Treat “bypass” vulnerabilities as potentially useful in multi-step attack chains: keep SmartScreen/ASR rules (where applicable), restrict local admin, and maintain strong application control so “local execution” is harder to achieve in the first place.

Key takeaway

Even though some articles describe this as a MOTW-related bypass, the reliable public CVE descriptions you can verify right now say “local security feature bypass in Windows Remote Assistance.” The correct response is still straightforward: patch systems promptly (January 2026 updates) and disable Remote Assistance where it’s not required. ([nvd.nist.gov](https://nvd.nist.gov/vuln/detail/CVE-2026-20824?utm_source=openai))

Sources

• NVD - CVE-2026-20824
• CVE-2026-20824
• https://www.cvedetails.com/cve/CVE-2026-20824/
• Windows Remote Assistance Vulnerability Allow Attacker to Bypass Security Features

 

[Divergent]

Remediation & Mitigation
Organizations should prioritize the January 2026 Cumulative Updates. If immediate patching is not feasible, Attack Surface Reduction (ASR) is recommended.

Apply Official Patches Deploy the relevant KB for your OS version immediately.

Windows 11 (23H2/24H2/25H2)
KB5073455 or KB5074109

Windows 10 (22H2)
KB5073724

Windows Server 2022
KB5073457 / KB5073450

Windows Server 2025
KB5073379

Attack Surface Reduction (Hardening)
If your environment does not utilize Windows Remote Assistance (msra.exe), disable the feature to eliminate the vector entirely.

PowerShell

# Check if Remote Assistance is allowed (0 = Disabled, 1 = Enabled)
Get-ItemProperty -Path 'HKLM:\SYSTEM\CurrentControlSet\Control\Remote Assistance' -Name 'fAllowToGetHelp'

# Disable Remote Assistance via Registry (Requires Admin)
Set-ItemProperty -Path 'HKLM:\SYSTEM\CurrentControlSet\Control\Remote Assistance' -Name 'fAllowToGetHelp' -Value 0

User Awareness
Reinforce training regarding unsolicited files. Since this exploit requires user interaction, a vigilant user remains a strong control. Warn specifically about files claiming to be "Remote Help" or "Support Tickets" from unverified sources.

References

CVE ID
CVE-2026-20824

Weakness ID
CWE-693 (Protection Mechanism Failure)

CVSS Score
5.5 (Medium/Important)

 

[Brownie2019]

Microsoft has released an out-of-band emergency update to resolve a critical issue affecting Remote Desktop connections on Windows client devices.

The problem emerged immediately following the installation of the January 2026 security update, identified as KB5074109. Administrators and users reported widespread credential prompt failures when attempting to sign in via the Windows App, significantly disrupting access to Azure Virtual Desktop and Windows 365 environments.

The original update, released on January 13, 2026, was intended to address routine security vulnerabilities and bugs for systems running specific Windows builds.

Full Article:

Microsoft January 2026 Security Update Causes Credential Prompt Failures in Remote Desktop Connections

Microsoft has released an out-of-band emergency update to resolve a critical issue affecting Remote Desktop connections on Windows client devices.

cybersecuritynews.com

 

[Bot]

Full Article:

Microsoft January 2026 Security Update Causes Credential Prompt Failures in Remote Desktop Connections

Microsoft has released an out-of-band emergency update to resolve a critical issue affecting Remote Desktop connections on Windows client devices.

cybersecuritynews.com

What you quoted matches a real, Microsoft-acknowledged regression from the January 2026 Patch Tuesday updates, and Microsoft has already published out-of-band (OOB) fixes.

What broke

After installing the January 13, 2026 cumulative/security update (for example KB5074109 on Windows 11 24H2/25H2), some users hit credential-prompt/sign-in failures when initiating Remote Desktop connections specifically via the “Windows App”, impacting Azure Virtual Desktop and Windows 365 connectivity. This is listed in Windows Release Health as a confirmed issue.

Microsoft’s OOB fix (released January 17, 2026)

Depending on the Windows version/build, the OOB update KB is different. Examples Microsoft has published include:

• Windows 11 24H2/25H2: KB5077744 (OOB) – includes a fix for the Remote Desktop/Windows App sign-in failures and is cumulative (includes the January 13 security content).
• Windows 11 23H2: KB5077797 (OOB) – also notes the Remote Desktop sign-in fix.
• Windows 10 21H2/22H2 (ESU): KB5077796 (OOB) – also notes the Remote Desktop sign-in fix.
• Windows Server: Microsoft also published an OOB track for Server builds addressing the same Remote Desktop sign-in symptom (example: KB5077793 for a Server build line).

Safe/standard mitigation while rolling out the fix

Microsoft’s documented workarounds (until the OOB is deployed everywhere) are:

• Use the “Remote Desktop client for Windows” (MSRDC) instead of the Windows App for AVD connections.
• Use the Windows App Web Client (web access) at windows.cloud.microsoft.

For orgs managing fleets (Intune/WSUS/ConfigMgr), the usual practical steps are:

• Pause/hold further deployment of the January 13 LCU to rings not yet impacted (to avoid spreading the outage).
• Prioritize deploying the relevant January 17 OOB cumulative update to affected endpoints (pilot first if possible).
• If business impact is severe and you cannot deploy the OOB quickly, consider uninstalling the January 13 LCU on impacted clients as a temporary measure (with the understanding you’re rolling back security fixes and should re-patch as soon as the OOB is deployed).

Sources

• Windows 11, version 25H2 known issues and notifications
• January 17, 2026—KB5077744 (OS Builds 26200.7627 and 26100.7627) Out-of-band - Microsoft Support
• January 17, 2026—KB5077797 (OS Build 22631.6494) Out-of-band - Microsoft Support
• January 17, 2026—KB5077796 (OS Builds 19045.6811 and 19044.6811) Out-of-band - Microsoft Support
• January 17, 2026—KB5077793 (OS Build 26100.32234) Out-of-band - Microsoft Support