CVE-2026-54777 (GCVE-0-2026-54777)

Vulnerability from cvelistv5 – Published: 2026-07-08 22:01 – Updated: 2026-07-09 12:57
VLAI
Title
CoreWCF NetNamedPipe transport accepts attach to a pre-existing named pipe instance
Summary
CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. Prior to 1.8.1 and 1.9.1, CoreWCF NetNamedPipe transport accepts attachment to a pre-existing named pipe instance, allowing local interception of NetNamedPipe traffic when an attacker races NamedPipeListener startup between shared memory GUID publication and service named pipe creation. This issue is fixed in versions 1.8.1 and 1.9.1.
Severity
6.5 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
  • CWE-665 - Improper Initialization
Assigner
References
Impacted products
Vendor Product Version
CoreWCF CoreWCF Affected: >= 1.9.0, < 1.9.1
Affected: < 1.8.1
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.
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  • 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.


Detection rules are retrieved from Rulezet.