CVE-2021-39207 Deserialization of Untrusted Data in parlai
Attackers can execute arbitrary code via unsafe YAML deserialization in the ParlAI framework, requiring users to upgrade or use SafeLoader.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-39207?
CVE-2021-39207 is a high-severity unsafe deserialization vulnerability in facebookresearch ParlAI, published on 10 Sep 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
parlai is a framework for training and evaluating AI models on a variety of openly available dialogue datasets. In affected versions the package is vulnerable to YAML deserialization attack caused by unsafe loading which leads to Arbitary code execution. This security bug is patched by avoiding unsafe loader users should update to version above v1.1.0. If upgrading is not possible then users can change the Loader used to SafeLoader as a workaround. See commit 507d066ef432ea27d3e201da08009872a2f37725 for details.
Weakness: CWE-502
Which versions are affected by CVE-2021-39207?
It affects 1 product.
Products include Facebook Parlai.
How do I fix CVE-2021-39207?
Upgrade to a fixed version.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2021-39207 being exploited?
There is no known exploitation of CVE-2021-39207 in the wild and no public exploit code.