jsonpickle through 1.4.2 allows remote code execution during deserialization of a malicious payload through the decode() function. This CVE is disputed by the project author as intended functionality.

References

• https://nvd.nist.gov/vuln/detail/CVE-2020-22083
• jsonpickle/jsonpickle#332
• jsonpickle/jsonpickle#332 (comment)
• https://access.redhat.com/security/cve/CVE-2020-22083
• https://gist.github.com/j0lt-github/bb543e77a1a10c33cb56cf23d0837874
• https://github.com/j0lt-github/python-deserialization-attack-payload-generator
• jsonpickle/jsonpickle#335
• https://versprite.com/blog/application-security/into-the-jar-jsonpickle-exploitation