Is there a public exploit for CVE-2021-43877?

No public exploit for CVE-2021-43877 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2021-43877?

CVE-2021-43877 scores CVSS 8.8 (v3.1), rated high. EPSS puts the chance of exploitation in the next 30 days at 0.73%.

What does CVE-2021-43877 affect?

CVE-2021-43877 affects Microsoft Microsoft Visual Studio 2022 version 17.0, Microsoft Visual Studio 2019 version 16.11 (includes 16.0 - 16.10), ASP.NET Core 6.0, Microsoft Visual Studio 2022 version 17.1, Microsoft Visual Studio 2019 version 16.9 (includes 16.0 - 16.8), ASP.NET Core 3.1.

8.8 High

ASP.NET Core and Visual Studio Elevation of Privilege Vulnerability

CVE-2021-43877

Assessment

CVSS: 8.8 (v3.1)
Severity: High
EPSS: 0.73% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 15 December 2021
Last updated: 2 November 2026
Affected: Microsoft · ASP.NET Core 3.1 · ASP.NET Core 5.0 · ASP.NET Core 6.0 · Microsoft Visual Studio 2019 version 16.11 (includes 16.0 - 16.10)
Assigner: microsoft

CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C

At the source

EUVD (ENISA)

References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43877

Community proofs of concept

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