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Fencer Intel
high 8.8

CVE-2021-44657 json

In StackStorm versions prior to 3.6.0, the jinja interpreter was not run in sandbox mode and thus allows execution of unsafe system command…

published 4y ago modified 4mo ago also EUVD-2021-31477

cvss
8.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.6%
EPSS 2.6% chance of exploitation in 30 days, percentile 85%
public exploits
0
none known

Summary

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.

Patch / fix

  • stackstorm stackstorm 3.6.0

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Exploit prediction

2.56% chance of exploitation in the next 30 days, higher than 85% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • podalirius.net https://podalirius.net/en/articles/python-vulnerabilities-code-execution-in-jinja-templates/ referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/pallets/jinja/issues/549 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 9.0 AV:N/AC:L/Au:S/C:C/I:C/A:C

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.