CVE-2024-27308: mio Use-After-Free — Fix

Description

Mio is a Metal I/O library for Rust. When using named pipes on Windows, mio will under some circumstances return invalid tokens that correspond to named pipes that have already been deregistered from the mio registry. The impact of this vulnerability depends on how mio is used. For some applications, invalid tokens may be ignored or cause a warning or a crash. On the other hand, for applications that store pointers in the tokens, this vulnerability may result in a use-after-free. For users of Tokio, this vulnerability is serious and can result in a use-after-free in Tokio. The vulnerability is Windows-specific, and can only happen if you are using named pipes. Other IO resources are not affected. This vulnerability has been fixed in mio v0.8.11. All versions of mio between v0.7.2 and v0.8.10 are vulnerable. Tokio is vulnerable when you are using a vulnerable version of mio AND you are using at least Tokio v1.30.0. Versions of Tokio prior to v1.30.0 will ignore invalid tokens, so they are not vulnerable. Vulnerable libraries that use mio can work around this issue by detecting and ignoring invalid tokens.

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CVSS v3.1 Score

7.5

HIGH

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

Weakness Type (CWE)

CWE-416 Use After Free

CWE-672 CWE-672

Affected Products

Vendor	Product	Versions
mio_project	mio	0.7.2 — 0.8.10
tokio	tokio	>= 1.30.0

References

Advisories & Patches

https://github.com/tokio-rs/mio/commit/90d4fe00df870acd3d38f3dc4face9aacab8fbb9 https://github.com/tokio-rs/mio/security/advisories/GHSA-r8w9-5wcg-vfj7 https://github.com/tokio-rs/mio/commit/90d4fe00df870acd3d38f3dc4face9aacab8fbb9 https://github.com/tokio-rs/mio/security/advisories/GHSA-r8w9-5wcg-vfj7

Other References

https://github.com/tokio-rs/mio/pull/1760 https://github.com/tokio-rs/tokio/issues/6369 https://github.com/tokio-rs/mio/pull/1760 https://github.com/tokio-rs/tokio/issues/6369

Frequently Asked Questions

What is CVE-2024-27308? +

Mio is a Metal I/O library for Rust. When using named pipes on Windows, mio will under some circumstances return invalid tokens that correspond to named pipes that have already been deregistered from the mio registry. The impact of this vulnerability depends on how mio is used. For some applications, invalid tokens may be ignored or cause a warning or a crash. On the other hand, for applications that store pointers in the tokens, this vulnerability may result in a use-after-free. For users of Tokio, this vulnerability is serious and can result in a use-after-free in Tokio. The vulnerability is Windows-specific, and can only happen if you are using named pipes. Other IO resources are not affected. This vulnerability has been fixed in mio v0.8.11. All versions of mio between v0.7.2 and v0.8.10 are vulnerable. Tokio is vulnerable when you are using a vulnerable version of mio AND you are using at least Tokio v1.30.0. Versions of Tokio prior to v1.30.0 will ignore invalid tokens, so they are not vulnerable. Vulnerable libraries that use mio can work around this issue by detecting and ignoring invalid tokens. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2024-27308? +

CVE-2024-27308 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-27308? +

CVE-2024-27308 affects products from mio_project, tokio, specifically: mio, tokio. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-27308? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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