6.5
MEDIUM CVSS 3.1
CVE-2026-54777
CoreWCF NetNamedPipe transport accepts attach to a pre-existing named pipe instance
Description

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.

INFO

Published Date :

July 8, 2026, 10:17 p.m.

Last Modified :

July 8, 2026, 10:17 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-54777 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update CoreWCF NetNamedPipe transport to a patched version to fix race condition.
  • Update CoreWCF to version 1.8.1 or later.
  • Update CoreWCF to version 1.9.1 or later.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-54777 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-54777 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-54777 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 08, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'CoreWCF', 'product': 'CoreWCF', 'versions': [{'status': 'affected', 'version': '>= 1.9.0, < 1.9.1'}, {'status': 'affected', 'version': '< 1.8.1'}]}]
    Added Description 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.
    Added CVSS V3.1 AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L
    Added CWE CWE-665
    Added CWE CWE-367
    Added Reference https://github.com/CoreWCF/CoreWCF/commit/8ed9c780c7c6fb22fa215c5771dee0c1e49596b7
    Added Reference https://github.com/CoreWCF/CoreWCF/commit/e7d225394fd429900dcbc445dcdd53b94e964077
    Added Reference https://github.com/CoreWCF/CoreWCF/releases/tag/v1.8.1
    Added Reference https://github.com/CoreWCF/CoreWCF/releases/tag/v1.9.1
    Added Reference https://github.com/CoreWCF/CoreWCF/security/advisories/GHSA-6jj2-4q5c-x8g6
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.