Code execution via RDP client heap overflow
Published Jul 14, 2026 · Updated Jul 14, 2026
Heap-based buffer overflow in Remote Desktop Client on affected Windows releases allows remote attackers to execute code over a network. The client accepts specially crafted responses from a malicious RDP server and corrupts heap memory, but Microsoft has not disclosed the affected parser or message type. Exploitation requires a user to initiate the RDP connection; successful code runs in the logged-on user's context.
Summary
What happened
Heap-based buffer overflow in Remote Desktop Client on affected Windows releases allows remote attackers to execute code over a network. The client accepts specially crafted responses from a malicious RDP server and corrupts heap memory, but Microsoft has not disclosed the affected parser or message type. Exploitation requires a user to initiate the RDP connection; successful code runs in the logged-on user's context.
The record
- CVE
- CVE-2026-54990
- Published
- Jul 14, 2026
- Updated
- Jul 14, 2026
- Vendor
- Microsoft
- Product
- Windows Server 2025 (Server Core installation)
- Classifications
- CWE-122, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 14, 2026CVE publishedPublication date reported by the CVE source.
- Jul 14, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=10.0.26100.0 <10.0.26100.33158
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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