CVE-2021-44657

Name: CVE-2021-44657
Creator: NVD / NIST
Published: 2021-12-15T15:15:11.597+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 2.47%

Last modified Jun 17, 2026

CVE-2021-44657 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. 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. EPSS estimates a 2.47% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

2.47%

82.5th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Stackstorm	Stackstorm	< 3.6.0

References

https://github.com/StackStorm/st2/pull/5359Patch, Third Party Advisory
https://github.com/pallets/jinja/issues/549Exploit, Issue Tracking, Third Party Advisory
https://podalirius.net/en/articles/python-vulnerabilities-code-execution-in-jinja-templates/Exploit, Third Party Advisory
https://stackstorm.com/2021/12/16/stackstorm-v3-6-0-released/Release Notes, Vendor Advisory
https://github.com/StackStorm/st2/pull/5359Patch, Third Party Advisory
https://github.com/pallets/jinja/issues/549Exploit, Issue Tracking, Third Party Advisory
https://podalirius.net/en/articles/python-vulnerabilities-code-execution-in-jinja-templates/Exploit, Third Party Advisory
https://stackstorm.com/2021/12/16/stackstorm-v3-6-0-released/Release Notes, Vendor Advisory

Timeline

Published: Dec 15, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-44657?

How severe is CVE-2021-44657?

CVE-2021-44657 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 2.47% probability of exploitation in the next 30 days.

How do I fix CVE-2021-44657?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-44657?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST