CVE-2026-62824

Remote Desktop is the feature people use to connect to another computer as if they were sitting in front of it. This vulnerability is a flaw in the Windows Remote Desktop Client that can be triggered by a specially made connection/session. If it’s triggered, an attacker may be able to run malicious code on your machine over the network.

This matters if your business uses or runs Windows 10, Windows Server 2012, Windows Server 2012 R2, or Windows Server 2016 systems with the Remote Desktop Client available and reachable in normal use.
It becomes a risk when an attacker can connect to you and deliver a crafted Remote Desktop session that the client processes; the attack is designed to be remote, and a victim action such as connecting/opening the session may be involved.

This is RED because it’s a remote code execution vulnerability in a core networking feature (Remote Desktop Client), and attackers with serious intent have been publicly associated with this kind of activity (Lazarus group) alongside active patching. There is no public exploit code on record, but you should not wait—patch availability is confirmed for all affected Windows versions, and the risk is driven by remote reachability and session handling.

Confirm whether you’re affected

1. On each relevant endpoint (Windows 10 / Windows Server 2012 / Windows Server 2012 R2 / Windows Server 2016), check the installed build.
   • On Windows, you can usually find the version/build under Settings → System → About (or by using system information tools).
2. Compare your build to the fixed versions from Microsoft:
   • Windows 10: fixed in 10.0.14393.9418
   • Windows Server 2016: fixed in 10.0.14393.9418
   • Windows Server 2012: fixed in 6.2.9200.26280
   • Windows Server 2012 R2: fixed in 6.3.9600.23338

Patch remediation (preferred)

3. Install the Microsoft security update for CVE-2026-62824 from the Microsoft Update Guide:
   • https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62824
4. Reboot if your patch process requires it, then re-check the build number to confirm it is at or above the fixed version for your OS.

Temporary workaround if patching is delayed

5. Reduce Remote Desktop exposure immediately:
   • Restrict inbound Remote Desktop access to only required IPs/users via firewall rules.
   • If Remote Desktop is not needed on a given endpoint, disable/turn off the Remote Desktop feature(s) there until patched.
6. Watch for unusual Remote Desktop session attempts and connection patterns around the time of patching (log review guidance should match how your organization tracks Remote Desktop connections).

What to monitor after patching

7. Confirm patch compliance (build number verification) across all affected endpoints.
8. Continue to monitor Remote Desktop connection logs for unexpected sources or repeated failed connection patterns.

Exploit/coverage notes

• No public exploit code is on record (so opportunistic public tooling is less likely), but this is still treated as active and high-risk due to the remote code execution nature and associated threat activity in the patch cycle.

CVE-2026-62824 is a high-severity (CVSS 8.8) stack-based buffer overflow (CWE-121) in the Windows Remote Desktop Client. The triggering mechanism is a crafted Remote Desktop session/stream that causes memory corruption when processed by the client, leading to remote code execution.

Findings provided: Microsoft has released fixed builds for each affected OS branch (Windows 10 / Windows Server 2016: 10.0.14393.9418; Windows Server 2012: 6.2.9200.26280; Windows Server 2012 R2: 6.3.9600.23338). KEV is not listed in CISA KEV and there is no public exploit code on record; however, press attention indicates patch-focused activity and the actor Lazarus group has been associated with the event. EPSS is predicted low (trend flat), but the RED urgency is driven by the confirmed availability of patches and the remote code execution risk in Remote Desktop Client processing.