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CVE-2026-42913NVD status: Modified

Remote Desktop client for Windows Desktop: Concurrent Execution using Shared Resource with Improper Synchronization

CVE-2026-42913 is a high-severity concurrent execution using shared resource with improper synchronization vulnerability in Remote Desktop client for Windows Desktop from Microsoft, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version 1.2.7214.0 as the first without the flaw, so updating Remote Desktop client for Windows Desktop to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.47% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Remote Desktop client for Windows Desktop to 1.2.7214.0 or a later version.
  2. Update Windows 11 version 23H2 to 10.0.22631.7219 or a later version.
  3. Update Windows 11 Version 24H2 to 10.0.26100.8655 or a later version.
  4. Read the advisory on msrc.microsoft.com for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  6. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
MicrosoftRemote Desktop client for Windows Desktop1.2.0.0 up to, but not including, 1.2.7214.01.2.7214.0
MicrosoftWindows 11 version 23H210.0.22631.0 up to, but not including, 10.0.22631.721910.0.22631.7219
MicrosoftWindows 11 Version 24H210.0.26100.0 up to, but not including, 10.0.26100.865510.0.26100.8655
MicrosoftWindows 11 Version 25H210.0.26200.0 up to, but not including, 10.0.26200.865510.0.26200.8655
MicrosoftWindows 11 version 26H110.0.28000.0 up to, but not including, 10.0.28000.226910.0.28000.2269
MicrosoftWindows Server 202210.0.20348.0 up to, but not including, 10.0.20348.525610.0.20348.5256
MicrosoftWindows Server 202510.0.26100.0 up to, but not including, 10.0.26100.3299510.0.26100.32995
MicrosoftWindows Server 2025 (Server Core installation)10.0.26100.0 up to, but not including, 10.0.26100.3299510.0.26100.32995
MicrosoftRemote Desktop Clientbefore 1.2.72141.2.7214
MicrosoftWindows 11 23h2before 10.0.22631.721910.0.22631.7219
MicrosoftWindows 11 24h2before 10.0.26100.865510.0.26100.8655
MicrosoftWindows 11 25h2before 10.0.26200.865510.0.26200.8655
MicrosoftWindows 11 26h1before 10.0.28000.226910.0.28000.2269

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H. Scored by CNA (microsoft.com).

Official description

Concurrent execution using shared resource with improper synchronization ('race condition') in Remote Desktop Client allows an unauthorized attacker to execute code over a network.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Concurrent Execution using Shared Resource with Improper Synchronization

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

How developers prevent this class of flaw

  • In languages that support it, use synchronization primitives. Only wrap these around critical code to minimize the impact on performance.
  • Use thread-safe capabilities such as the data access abstraction in Spring.
  • Minimize the usage of shared resources in order to remove as much complexity as possible from the control flow and to reduce the likelihood of unexpected conditions occurring. Additionally, this will minimize the amount of synchronization necessary and may even help to reduce the likelihood of a denial of service where an attacker may be able to repeatedly trigger a critical section (CWE-400).

More Concurrent Execution using Shared Resource with Improper Synchronization vulnerabilities (CWE-362)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Remote Desktop client for Windows Desktop

All Remote Desktop client for Windows Desktop vulnerabilities

Recent Concurrent Execution using Shared Resource with Improper Synchronization vulnerabilities

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