Tokio's reject_remote_clients configuration may get dropped when creating a Windows named pipe

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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`.

Source published

4 Jan 2023 21:47:09 UTC

Source modified

10 Mar 2025 21:32:32 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L

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`.

Source published

Jan 4, 2023, 9:47:09 PM (timezone not stated)

Source modified

Mar 10, 2025, 9:32:32 PM (timezone not stated)

Observed here

10 Nov 2026 01:18:31 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L

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`.

Source published

4 Jan 2023 22:15:09 UTC

Source modified

17 Jun 2026 05:35:30 UTC

Observed here

24 Oct 2026 21:17:28 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L

CVSS 3.1 · [email protected] · Primary · 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

### Impact 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. This also applies if `reject_remote_clients` is not explicitly set as this is the default configuration and is cleared by calling `pipe_mode`. Remote clients may only access the named pipe if the named pipe's associated path is accessible via a publically shared folder (SMB). ### Patches The following versions have been patched: * 1.23.1 * 1.20.3 * 1.18.4 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. ### Workarounds Ensure that `pipe_mode` is set **first** after initializing a `ServerOptions`. For example: ```rust let mut opts = ServerOptions::new(); opts.pipe_mode(PipeMode::Message); opts.reject_remote_clients(true); ``` ### References https://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-createnamedpipea#pipe_reject_remote_clients

Source published

6 Jan 2023 21:40:58 UTC

Source modified

10 Sep 2026 03:49:51 UTC

Observed here

24 Oct 2026 13:19:54 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L

Publisher rating · MODERATE

On Windows, configuring a named pipe server with [pipe_mode] will force [ServerOptions]::[reject_remote_clients] as `false`. This drops any intended explicit configuration for the [reject_remote_clients] that may have been set as `true` previously. The default setting of [reject_remote_clients] is normally `true` meaning the default is also overridden as `false`. ## Workarounds Ensure that [pipe_mode] is set first after initializing a [ServerOptions]. For example: ```rust let mut opts = ServerOptions::new(); opts.pipe_mode(PipeMode::Message); opts.reject_remote_clients(true); ``` [ServerOptions]: https://docs.rs/tokio/latest/tokio/net/windows/named_pipe/struct.ServerOptions.html [pipe_mode]: https://docs.rs/tokio/latest/tokio/net/windows/named_pipe/struct.ServerOptions.html#method.pipe_mode [reject_remote_clients]: https://docs.rs/tokio/latest/tokio/net/windows/named_pipe/struct.ServerOptions.html#method.reject_remote_clients

Source published

4 Jan 2023 12:00:00 UTC

Source modified

12 Oct 2026 18:00:06 UTC

Observed here

24 Oct 2026 13:19:54 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.