Visual Studio: Remote code execution via heap-based buffer overflow
Summary
A heap-based buffer overflow in Visual Studio allows an unauthorized attacker to execute code over a network. The CNA record also lists Microsoft .NET 8.0, 9.0, 10.0 and 11.0 installed on Windows as affected. According to the CVSS vector, exploitation requires user interaction but no privileges.
Affected
- Microsoft .NET 8.0 on Windows: 8.0.0 to before 8.0.34
- Microsoft .NET 9.0 on Windows: 9.0.0 to before 9.0.23
- Microsoft .NET 10.0 on Windows: 10.0.0 to before 10.0.15
- Microsoft .NET 11.0 on Windows: 11.0.0-preview.1 to before 11.0.0
- Visual Studio 2026 version 18.11: 18.11.0 to before 18.11.4
- Visual Studio 2026 version 18.12: affected range as listed by the CNA is internally inconsistent; exact build unknown
Fixed in
- .NET 8.0.34, 9.0.23, 10.0.15 and 11.0.0 (November 10, 2026 security release; to be confirmed in the Microsoft advisory)
- Visual Studio 2026 18.11: fixed build unknown (check MSRC; a third-party source suggests 18.11.4, not verified)
- Visual Studio 2026 18.12: fixed build unknown (check MSRC)
Workaround
- Unknown. No specific workaround found in the sources.
Exploitation
- No evidence of exploitation in the wild found at publication.
- No public proof-of-concept found.
- Not confirmed as listed in CISA KEV; recheck the catalog.
- CNA temporal metrics: exploit maturity Unproven, report confidence Confirmed.
- NVD status: Awaiting Analysis.
Our recommendation
- Install the .NET security updates for your installed versions (8.0.34, 9.0.23, 10.0.15, 11.0.0 or later).
- Update Visual Studio 2026 to the build listed in the MSRC Security Update Guide once confirmed.
- Prioritise developer workstations and build servers with Visual Studio, and Windows servers running .NET applications.
- Check the MSRC entry and CISA KEV again in the coming days and monitor for exploitation.
Information from Microsoft (Patch Tuesday November 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- MSRC Security Update Guide: CVE-2026-118745 msrc.microsoft.com
- CVE Record CVE-2026-118745 (CVE Program) www.cve.org
- .NET core release notes PR (November 2026 security release) github.com
- Strix AI: CVE-2026-118745 (third-party, unverified) www.strix.ai
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 10 Nov 2026, 21:40.
Original description (NVD)
Heap-based buffer overflow in Visual Studio allows an unauthorized attacker to execute code over a network.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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