Remote code execution via heap buffer overflow
Published Jun 9, 2026 · Updated Jun 9, 2026
Heap-based buffer overflow in Microsoft's Remote Desktop Client allows remote attackers to execute code through a malicious server. Microsoft has not disclosed the affected parser or the operation that writes beyond the heap allocation while processing server-controlled data. Exploitation requires a user to connect the client to a malicious or compromised Remote Desktop server, after which code runs in the user's context.
Summary
What happened
Heap-based buffer overflow in Microsoft's Remote Desktop Client allows remote attackers to execute code through a malicious server. Microsoft has not disclosed the affected parser or the operation that writes beyond the heap allocation while processing server-controlled data. Exploitation requires a user to connect the client to a malicious or compromised Remote Desktop server, after which code runs in the user's context.
The record
- CVE
- CVE-2026-42992
- Published
- Jun 9, 2026
- Updated
- Jun 9, 2026
- Vendor
- Microsoft
- Product
- Windows Server 2019
- Classifications
- CWE-122, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 9, 2026CVE publishedPublication date reported by the CVE source.
- Jun 9, 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=10.0.17763.0 <10.0.17763.8880
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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