How severe is CVE-2021-41127?

CVE-2021-41127 has a CVSS score of 7.1/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2021-41127?

CVE-2021-41127 affects the following packages: rasa (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2021-41127?

Update rasa to 2.8.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-41127 is resolved across your whole dependency graph.

How do I detect CVE-2021-41127 in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for rasa. 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.

How do I mitigate CVE-2021-41127 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2021-41127?

O3 pinpoints whether CVE-2021-41127 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2021-41127 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-41127 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2021-41127?

CVE-2021-41127 has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 50th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2021-41127?

CVE-2021-41127 is classified as Path Traversal (CWE-22), CWE-23 (CWE-23). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2021-41127 published, and has it been updated?

CVE-2021-41127 was published on October 21, 2021 and was last updated on April 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍 PyPI

CVE-2021-41127

HIGH

Maliciously Crafted Model Archive Can Lead To Arbitrary File Write

Also known asGHSA-4365-fhm5-qcrxPYSEC-2021-381

Published

Oct 21, 2021

Updated

Apr 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk50th percentile+0.34%

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.

Blast Radius

1 pkg affected

🐍rasa

Real-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

Rasa is an open source machine learning framework to automate text-and voice-based conversations. In affected versions a vulnerability exists in the functionality that loads a trained model tar.gz file which allows a malicious actor to craft a model.tar.gz file which can overwrite or replace bot files in the bot directory. The vulnerability is fixed in Rasa 2.8.10. For users unable to update ensure that users do not upload untrusted model files, and restrict CLI or API endpoint access where a malicious actor could target a deployed Rasa instance.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`rasa`	all versions	2.8.10

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for rasa. 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 rasa to 2.8.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-41127 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-2021-41127 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-2021-41127. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Rasa is an open source machine learning framework to automate text-and voice-based conversations. In affected versions a vulnerability exists in the functionality that loads a trained model `tar.gz` file which allows a malicious actor to craft a `model.tar.gz` file which can overwrite or replace bot files in the bot directory. The vulnerability is fixed in Rasa 2.8.10. For users unable to update ensure that users do not upload untrusted model files, and restrict CLI or API endpoint access where a malicious actor could target a deployed Rasa instance.

O3 Security · Impact-Aware SCA

Is CVE-2021-41127 in your dependencies?

O3 detects CVE-2021-41127 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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