CVE-2021-27213

CRITICAL 9.8CVE-2021-27213 · Published 14/02/2021 · updated 17/06/2026

In short

CVE-2021-27213 is a CRITICAL (CVSS 9.8) vulnerability affecting pystemon (pystemon project).
Chance of exploitation in the next 30 days (EPSS): 2.6%, higher than 85.5% of all vulnerabilities.
Fix: update to 2021-02-13 or later.

Package	Affected versions	Patched versions
pystemon pystemon_project	`< 2021-02-13`	`2021-02-13`

config.py in pystemon before 2021-02-13 allows code execution via YAML deserialization because SafeLoader and safe_load are not used.

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