CVE-2021-44657

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-12-15 · updated 2026-06-17

Description

In StackStorm versions prior to 3.6.0, the jinja interpreter was not run in sandbox mode and thus allows execution of unsafe system commands. Jinja does not enable sandboxed mode by default due to backwards compatibility. Stackstorm now sets sandboxed mode for jinja by default.

Affected products

Stackstorm: before 3.6.0 — fixed in 3.6.0

How to fix

Upgrade to a fixed version: Stackstorm 3.6.0. Check the vendor advisory for mitigations.

References

https://github.com/StackStorm/st2/pull/5359
https://github.com/pallets/jinja/issues/549
https://podalirius.net/en/articles/python-vulnerabilities-code-execution-in-jinja-templates/
https://stackstorm.com/2021/12/16/stackstorm-v3-6-0-released/
https://github.com/StackStorm/st2/pull/5359
https://github.com/pallets/jinja/issues/549
https://podalirius.net/en/articles/python-vulnerabilities-code-execution-in-jinja-templates/
https://stackstorm.com/2021/12/16/stackstorm-v3-6-0-released/

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