CVE-2026-42904: CWE-122: Heap-based Buffer Overflow in Microsoft Windows 10 Version 21H2
Heap-based buffer overflow in Windows TCP/IP allows an unauthorized attacker to elevate privileges over an adjacent network.
AI Analysis
Technical Summary
This vulnerability involves a heap-based buffer overflow in the Windows TCP/IP implementation in Windows 10 Version 21H2 (build 10.0.19044.0). An attacker with access to an adjacent network can exploit this flaw to escalate privileges, potentially gaining elevated control over the affected system. Microsoft has published an official fix to address this issue.
Potential Impact
Successful exploitation can lead to complete compromise of confidentiality, integrity, and availability of the affected system due to privilege escalation. The vulnerability requires network adjacency but no user interaction or privileges to exploit. There are no known exploits in the wild at the time of publication.
Mitigation Recommendations
An official patch is available from Microsoft and should be applied promptly to remediate this vulnerability. Refer to the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42904 for detailed update instructions.
CVE-2026-42904: CWE-122: Heap-based Buffer Overflow in Microsoft Windows 10 Version 21H2
Description
Heap-based buffer overflow in Windows TCP/IP allows an unauthorized attacker to elevate privileges over an adjacent network.
CVSS v3.1
Score 9.6critical
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a heap-based buffer overflow in the Windows TCP/IP implementation in Windows 10 Version 21H2 (build 10.0.19044.0). An attacker with access to an adjacent network can exploit this flaw to escalate privileges, potentially gaining elevated control over the affected system. Microsoft has published an official fix to address this issue.
Potential Impact
Successful exploitation can lead to complete compromise of confidentiality, integrity, and availability of the affected system due to privilege escalation. The vulnerability requires network adjacency but no user interaction or privileges to exploit. There are no known exploits in the wild at the time of publication.
Mitigation Recommendations
An official patch is available from Microsoft and should be applied promptly to remediate this vulnerability. Refer to the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42904 for detailed update instructions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-04-30T22:35:54.968Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42904","vendor":"Microsoft"}]
Threat ID: 6a284cc08dd33fbd856646df
Added to database: 6/9/2026, 5:26:24 PM
Last enriched: 6/9/2026, 11:12:13 PM
Last updated: 6/10/2026, 6:27:00 AM
Views: 5
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