GHSA-mj6p-44ch-cq69 is a low-severity (CVSS 3.3) CWE-367 vulnerability in uu_mkdir. A fix is available for uu_mkdir — see the affected versions and patch details below.
mkdir: -m exposes directory with umask perms before chmod (race window)
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 GHSA-mj6p-44ch-cq69.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-mj6p-44ch-cq69 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
uu_mkdirReal-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 mkdir utility in uutils coreutils incorrectly applies permissions when using the -m flag by creating a directory with umask-derived permissions (typically 0755) before subsequently changing them to the requested mode via a separate chmod system call. In multi-user environments, this introduces a brief window where a directory intended to be private is accessible to other users, potentially leading to unauthorized data access.
Zellic finding 3.48. Reported in the Zellic uutils coreutils Program Security Assessment (for Canonical, Jan 2026), audited commit 3a07ffc5a9bd4c283e75afa548ba1f1957bad242.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | uu_mkdir | all versions | 0.6.0cargo update -p uu_mkdir --precise 0.6.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for uu_mkdir, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update uu_mkdir to 0.6.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mj6p-44ch-cq69 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-mj6p-44ch-cq69 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-mj6p-44ch-cq69. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-mj6p-44ch-cq69 in your dependencies?
O3 Security finds GHSA-mj6p-44ch-cq69 across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.