CVE-2026-21218 (GCVE-0-2026-21218)

Vulnerability from cvelistv5 – Published: 2026-02-10 17:51 – Updated: 2026-02-13 22:30
VLAI?
Title
.NET Spoofing Vulnerability
Summary
Improper handling of missing special element in .NET allows an unauthorized attacker to perform spoofing over a network.
Severity ?
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C
CWE
  • CWE-166 - Improper Handling of Missing Special Element
Assigner
References
Impacted products
Vendor Product Version
Microsoft .NET 10.0 Affected: 10.0.0 , < 10.0.3 (custom)
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    Microsoft .NET 8.0 Affected: 8.0.0 , < 8.0.24 (custom)
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    Microsoft .NET 9.0 Affected: 9.0.0 , < 9.0.13 (custom)
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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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