CVE-2021-43811 is a high-severity (CVSS 7.8) Code Injection vulnerability in sockeye. 1 public exploit reference exists, so weaponization risk is real. A fix is available for sockeye — see the affected versions and patch details below.
Code injection via unsafe YAML loading
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2021-43811 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,386 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
sockeyeReal-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
Impact
Sockeye uses YAML to store model and data configurations on disk. Versions below 2.3.24 use unsafe YAML loading, which can be made to execute arbitrary code embedded in config files.
An attacker can add malicious code to the config file of a trained model and attempt to convince users to download and run it. If users run the model, the embedded code will run locally.
Patches
The issue is fixed in version 2.3.24 and above by #964.
For more information
If you have any questions or comments about this advisory:
- Open an issue in awslabs/sockeye
- Email us at sockeye-dev
Attribution
This vulnerability was reported by Masatoshi Yoshizawa of yamory Security Team.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | sockeye | all versions | 2.3.24pip install --upgrade 'sockeye==2.3.24' |
Affected Products
sockeyeamazonResearch 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 sockeye, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update sockeye to 2.3.24 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-43811 is resolved across your whole dependency graph.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.
Frequently Asked Questions
Is CVE-2021-43811 in your dependencies?
Find it across PyPI, including transitive dependencies.