How severe is CVE-2024-51756?

No CVSS score has been assigned to CVE-2024-51756 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2024-51756?

CVE-2024-51756 affects the following packages: cap-std (crates.io), cap-async-std (crates.io), cap-primitives (crates.io). Ecosystems affected: crates.io.

How do I fix CVE-2024-51756?

Update cap-std to 3.4.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-51756 is resolved across your whole dependency graph.

How do I detect CVE-2024-51756 in my crates.io dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for cap-std, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2024-51756 if there is no patch (or I can't update yet)?

Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Is CVE-2024-51756 actively exploited in the wild?

No public exploit code has been indexed for CVE-2024-51756 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2024-51756?

CVE-2024-51756 has an EPSS (Exploit Prediction Scoring System) score of 0.6%, placing it in the 48th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2024-51756?

CVE-2024-51756 is classified as Path Traversal (CWE-22). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2024-51756 published, and has it been updated?

CVE-2024-51756 was published on November 5, 2024 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🦀 crates.io

Not in CISA KEV

CVE-2024-51756 — cap-std

Fix: bytecodealliance/cap-std@dcc3818

CVE-2024-51756 is a Path Traversal vulnerability in cap-std. A fix is available for cap-std — see the affected versions and patch details below.

cap-std doesn't fully sandbox all the Windows device filenames

Also known asGHSA-hxf5-99xg-86hwRUSTSEC-2024-0445

Published

Nov 5, 2024

Updated

Oct 28, 2026

Affected

3 pkgs

Patched

3 / 3

Exploits

None indexed

Exploitation data as of Nov 5, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2024-51756.

EPSS Exploitation Probability

via FIRST.org ↗

0.6%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs48th percentile — riskier than 48% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

3 pkgs affected

🦀cap-std🦀cap-async-std🦀cap-primitives

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.

Description

The cap-std project is organized around the eponymous cap-std crate, and develops libraries to make it easy to write capability-based code. cap-std's filesystem sandbox implementation on Windows blocks access to special device filenames such as "COM1", "COM2", "LPT0", "LPT1", and so on, however it did not block access to the special device filenames which use superscript digits, such as "COM¹", "COM²", "LPT⁰", "LPT¹", and so on. Untrusted filesystem paths could bypass the sandbox and access devices through those special device filenames with superscript digits, and through them provide access peripheral devices connected to the computer, or network resources mapped to those devices. This can include modems, printers, network printers, and any other device connected to a serial or parallel port, including emulated USB serial ports. The bug is fixed in #371, which is published in cap-primitives 3.4.1, cap-std 3.4.1, and cap-async-std 3.4.1. There are no known workarounds for this issue. Affected Windows users are recommended to upgrade.

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`cap-std`	all versions	3.4.1`cargo update -p cap-std --precise 3.4.1`
🦀crates.io	`cap-async-std`	all versions	3.4.1`cargo update -p cap-async-std --precise 3.4.1`
🦀crates.io	`cap-primitives`	all versions	3.4.1`cargo update -p cap-primitives --precise 3.4.1`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for cap-std, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update cap-std to 3.4.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-51756 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Frequently Asked Questions

The cap-std project is organized around the eponymous `cap-std` crate, and develops libraries to make it easy to write capability-based code. cap-std's filesystem sandbox implementation on Windows blocks access to special device filenames such as "COM1", "COM2", "LPT0", "LPT1", and so on, however it did not block access to the special device filenames which use superscript digits, such as "COM¹", "COM²", "LPT⁰", "LPT¹", and so on. Untrusted filesystem paths could bypass the sandbox and access devices through those special device filenames with superscript digits, and through them provide acces

O3 Security · Impact-Aware SCA

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