What is GHSA-4Q83-7CQ4-P6WG?

GHSA-4Q83-7CQ4-P6WG is a low-severity security vulnerability in tokio (rust), affecting versions >= 1.21.0, < 1.24.2. It is fixed in 1.24.2, 1.20.4, 1.18.5.

Which versions of tokio are affected by GHSA-4Q83-7CQ4-P6WG?

tokio (rust) versions >= 1.21.0, < 1.24.2 is affected.

Is there a fix for GHSA-4Q83-7CQ4-P6WG?

Yes. GHSA-4Q83-7CQ4-P6WG is fixed in 1.24.2, 1.20.4, 1.18.5. Upgrade to this version or later.

Is GHSA-4Q83-7CQ4-P6WG exploitable, and should I be worried?

Whether GHSA-4Q83-7CQ4-P6WG is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether GHSA-4Q83-7CQ4-P6WG is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

GHSA-4Q83-7CQ4-P6WG in tokio

Q: Which versions of tokio are affected by GHSA-4Q83-7CQ4-P6WG?

tokio (rust) versions >= 1.21.0, < 1.24.2 is affected.

Q: Is there a fix for GHSA-4Q83-7CQ4-P6WG?

Yes. GHSA-4Q83-7CQ4-P6WG is fixed in 1.24.2, 1.20.4, 1.18.5. Upgrade to this version or later.

Q: Is GHSA-4Q83-7CQ4-P6WG exploitable, and should I be worried?

Whether GHSA-4Q83-7CQ4-P6WG is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether GHSA-4Q83-7CQ4-P6WG is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix GHSA-4Q83-7CQ4-P6WG?

Upgrade: tokio to 1.24.2 or later, tokio to 1.20.4 or later, tokio to 1.18.5 or later.

Summary

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

tokio::io::ReadHalf<T>::unsplit can violate the Pin contract

The soundness issue is described in the tokio/issues#5372

Specific set of conditions needed to trigger an issue (a !Unpin type in ReadHalf)
is unusual, combined with the difficulty of making any arbitrary use-after-free
exploitable in Rust without doing a lot of careful alignment of data types in
the surrounding code.

The tokio feature io-util is also required to be enabled to trigger this
soundness issue.

Thanks to zachs18 reporting the issue to Tokio team responsibly and taiki-e
and carllerche appropriately responding and fixing the soundness bug.

Tokio before 0.2.0 used futures 0.1 that did not have Pin, so it is not
affected by this issue.

Impact

Affected versions

tokio (>= 1.21.0, < 1.24.2) tokio (>= 1.19.0, < 1.20.4) tokio (>= 0.2.0, < 1.18.5)

Security releases

tokio → 1.24.2 (rust) tokio → 1.20.4 (rust) tokio → 1.18.5 (rust)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

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Remediation advice

Upgrade the following packages to resolve this vulnerability:

tokio to 1.24.2 or later; tokio to 1.20.4 or later; tokio to 1.18.5 or later

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is GHSA-4Q83-7CQ4-P6WG? GHSA-4Q83-7CQ4-P6WG is a low-severity security vulnerability in tokio (rust), affecting versions >= 1.21.0, < 1.24.2. It is fixed in 1.24.2, 1.20.4, 1.18.5.
Which versions of tokio are affected by GHSA-4Q83-7CQ4-P6WG? tokio (rust) versions >= 1.21.0, < 1.24.2 is affected.
Is there a fix for GHSA-4Q83-7CQ4-P6WG? Yes. GHSA-4Q83-7CQ4-P6WG is fixed in 1.24.2, 1.20.4, 1.18.5. Upgrade to this version or later.
Is GHSA-4Q83-7CQ4-P6WG exploitable, and should I be worried? Whether GHSA-4Q83-7CQ4-P6WG is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether GHSA-4Q83-7CQ4-P6WG is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix GHSA-4Q83-7CQ4-P6WG?
- Upgrade tokio to 1.24.2 or later
- Upgrade tokio to 1.20.4 or later
- Upgrade tokio to 1.18.5 or later

Other vulnerabilities in tokio

CVE-IDSeverityPackage summary

GHSA-RR8G-9FPQ-6WMGLowtokio: Tokio broadcast channel calls clone in parallel, but does not require `Sync`CVE-2023-22466Mediumtokio: Tokio reject_remote_clients configuration may get dropped when creating a Windows named pipe CVE-2021-45710Hightokio: Race Condition in tokio CVE-2021-38191Mediumtokio: Race condition in tokio