What’s Vulnerable › Vulnerabilities

CVE-2023-22466: Tokio's reject_remote_clients configuration may get dropped when creating a Windows named pipe

• Severity: medium (CVSS 5.4 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-01-04 · updated 2026-06-17
• Weakness: CWE-665

Description

Tokio is a runtime for writing applications with Rust. Starting with version 1.7.0 and prior to versions 1.18.4, 1.20.3, and 1.23.1, when configuring a Windows named pipe server, setting `pipe_mode` will reset `reject_remote_clients` to `false`. If the application has previously configured `reject_remote_clients` to `true`, this effectively undoes the configuration. Remote clients may only access the named pipe if the named pipe's associated path is accessible via a publicly shared folder (SMB). Versions 1.23.1, 1.20.3, and 1.18.4 have been patched. The fix will also be present in all releases starting from version 1.24.0. Named pipes were introduced to Tokio in version 1.7.0, so releases older than 1.7.0 are not affected. As a workaround, ensure that `pipe_mode` is set first after initializing a `ServerOptions`.

Affected products

• tokio-rs tokio: from 1.7.0 before 1.18.4; from 1.19.0 before 1.20.3; from 1.21.0 before 1.23.1 — fixed in 1.18.4, 1.20.3, 1.23.1

How to fix

Upgrade to a fixed version: tokio-rs tokio 1.18.4, 1.20.3, 1.23.1. Check the vendor advisory for mitigations.

References

• https://github.com/tokio-rs/tokio/pull/5336
• https://github.com/tokio-rs/tokio/releases/tag/tokio-1.23.1
• https://github.com/tokio-rs/tokio/security/advisories/GHSA-7rrj-xr53-82p7
• https://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-createnamedpipea#pipe_reject_remote_clients
• https://github.com/tokio-rs/tokio/pull/5336
• https://github.com/tokio-rs/tokio/releases/tag/tokio-1.23.1
• https://github.com/tokio-rs/tokio/security/advisories/GHSA-7rrj-xr53-82p7
• https://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-createnamedpipea#pipe_reject_remote_clients

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