GHSA-mhhf-vgwh-fw9h is a medium-severity (CVSS 5.9) CWE-338 vulnerability in passeo. A fix is available for passeo — see the affected versions and patch details below.
Passeo uses insecure random number generator
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-mhhf-vgwh-fw9h 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 379,145 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
passeoReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Passeo is an open source python password generator. Versions prior to 1.0.5 rely on the python random library for random value selection. The python random library warns that it should not be used for security purposes due to its reliance on a non-cryptographically secure random number generator. As a result a motivated attacker may be able to guess generated passwords. This issue has been addressed in version 1.0.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | passeo | all versions | 1.0.5pip install --upgrade 'passeo==1.0.5' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for passeo, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update passeo to 1.0.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mhhf-vgwh-fw9h 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-mhhf-vgwh-fw9h can be triaged on real exposure rather than presence alone.
Tailored to GHSA-mhhf-vgwh-fw9h. 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-mhhf-vgwh-fw9h in your dependencies?
O3 Security finds GHSA-mhhf-vgwh-fw9h across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.