CVE-2026-47211
Fix: Q00/ouroboros@4e70b76CVE-2026-47211 is a CWE-426 vulnerability in ouroboros-ai. O3 Security confirms whether CVE-2026-47211 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Ouroboros: Remote Code Execution via Untrusted Project-Directory .env
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- 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-2026-47211.
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.
Real-World Exposure
ouroboros-aiReal-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
Ouroboros is a local-first runtime for AI coding agents that records their actions and applies user-defined policies to constrain behavior. In versions prior to 0.39.0, if a user clones a malicious repository and runs Ouroboros commands within that directory, it can lead to arbitrary code execution and potential system takeover. The vulnerability stems from Ouroboros loading the .env file from the current working directory. Execution-affecting environment variables such as OUROBOROS_CLI_PATH, OPENCODE_CLI_PATH, and other backend selectors are accepted directly from this local .env. An attacker can include a malicious script in the repository and point the CLI path variable to it (e.g., OUROBOROS_CLI_PATH=./malicious_script.sh). When the user executes a command like ouroboros init or any command that instantiates the adapter, the malicious script is executed instead of the intended CLI. This issue has been fixed in version 0.39.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | ouroboros-ai | all versions | 0.39.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ouroboros-ai. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update ouroboros-ai to 0.39.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-47211 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 pinpoints whether CVE-2026-47211 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-47211. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-47211 in your dependencies?
O3 detects CVE-2026-47211 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.