CVE-2024-53899 is a high-severity (CVSS 8.4) CWE-77 vulnerability in virtualenv. 1 public exploit reference exists, so weaponization risk is real. A fix is available for virtualenv — see the affected versions and patch details below.
virtualenv allows command injection through activation scripts for a virtual environment
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-53899.
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
CVE-2024-53899 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
virtualenvReal-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
virtualenv before 20.26.6 allows command injection through the activation scripts for a virtual environment. Magic template strings are not quoted correctly when replacing. NOTE: this is not the same as CVE-2024-9287.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | virtualenv | all versions | 20.26.6pip install --upgrade 'virtualenv==20.26.6' |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for virtualenv, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update virtualenv to 20.26.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-53899 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 CVE-2024-53899 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-53899. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 7 Extended Lifecycle Support | python-virtualenv-0:15.1.0-7.el7_9.1 | RHSA-2024:11048 |
| Red Hat Enterprise Linux 8 | python36:3.6-8100020241203074044.4c5117ad | RHSA-2024:10953 |
| Red Hat Enterprise Linux 8.2 Advanced Update Support | python36:3.6-8020020241213084804.606b8f18 | RHSA-2024:11091 |
| Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | python36:3.6-8040020241213073301.9bf6f064 | RHSA-2025:0002 |
| Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | python36:3.6-8060020241213062726.448f2761 | RHSA-2024:11094 |
| Red Hat Enterprise Linux 8.8 Extended Update Support | python36:3.6-8080020241205132428.075014fc | RHSA-2024:11093 |
| Red Hat OpenShift Dev Spaces 3 Containers | devspaces/udi-rhel9:3.18-1 | RHSA-2025:0892 |
Frequently Asked Questions
Is CVE-2024-53899 in your dependencies?
O3 Security finds CVE-2024-53899 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.