# `tokio::io::ReadHalf<T>::unsplit` is Unsound

Source: https://junglewise.ai/threats/tokio-io-readhalf-t-unsplit-is-unsound-68916389  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2023-02-04  
License: CC BY 4.0 with a link back

Severity: info · Published 2023-02-04

`tokio::io::ReadHalf<T>::unsplit` is Unsound

Technologies: [tokio (crates.io)](https://junglewise.ai/threats/technologies/tokio). Vendors: [crates.io](https://junglewise.ai/threats/vendors/crates-io).

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** Informational severity, published 4 February 2023.

**Which products and versions are affected?** tokio (crates.io) SEMVER:introduced=1.21.0,fixed=1.24.2.

**Is there a fix for This vulnerability?** Yes. tokio (crates.io): upgrade to 1.24.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected?** Check whether you run tokio (crates.io) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- tokio (crates.io): upgrade to 1.24.2 or later

  ```sh
  cargo update -p tokio
  ```


## Affected products

- tokio (crates.io) SEMVER:introduced=1.21.0,fixed=1.24.2

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- [Tokio race condition in Interval time driver](https://junglewise.ai/threats/rustsec-2026-0384-race-condition-in-tokio-time-interval-on-tokio-v1-54-c6906742)
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- [RUSTSEC-2025-0023 - Broadcast channel calls clone in parallel, but does not require `Sync`](https://junglewise.ai/threats/rustsec-2025-0023-broadcast-channel-calls-clone-in-parallel-but-does-22da8233)