CVE-2024-27308 | Mio's tokens for named pipes may be delivered after deregistration

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.

Published: 2024-03-06 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2024-27308 is rated Moderate Risk (56.8/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.94%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2024-27308

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-10 0.96% 0.94% -0.03%
2 2026-05-28 0.94% 0.96% +0.03%
3 2026-05-06 0.94%

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-27308

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 3.6 [email protected]
9.1 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.2 [email protected]

Weakness enumeration for CVE-2024-27308

GitHub Security Advisory for CVE-2024-27308

GHSA-r8w9-5wcg-vfj7 · Severity: high · Ecosystem: rust — Mio's tokens for named pipes may be delivered after deregistration

OS Trackers for CVE-2024-27308

vendor priority summary link
debian unimportant CVE-2024-27308 unimportant priority: Debian including 2 source packages (rust-mio, rust-mio-0.6), 9 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 9. https://security-tracker.debian.org/tracker/CVE-2024-27308
ubuntu medium CVE-2024-27308 medium priority: Ubuntu including 2 source packages (rust-mio, rust-mio-0.6), 10 status rows across 5 suites (focal, jammy, mantic, noble, upstream): not-affected 9, DNE 1. https://ubuntu.com/security/CVE-2024-27308

Affected software / configurations for CVE-2024-27308

Vendor Product Version Raw CPE
mio_project mio >= 0.7.2, <= 0.8.10 cpe:2.3:a:mio_project:mio:*:*:*:*:*:rust:*:*
tokio tokio >= 1.30.0 cpe:2.3:a:tokio:tokio:*:*:*:*:*:rust:*:*

References for CVE-2024-27308

cvelogic Threat Intelligence