CVE-2021-28667
StackStorm st2 Infinite Loop Condition
StackStorm before 3.4.1, in some situations, has an infinite loop that consumes all available memory and disk space. This can occur if Python 3.x is used, the locale is not utf-8, and there is an attempt to log Unicode data (from an action or rule name).
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
StackStorm before 3.4.1, in some situations, has an infinite loop that consumes all available memory and disk space. This can occur if Python 3.x is used, the locale is not utf-8, and there is an attempt to log Unicode data (from an action or rule name).
- Record
CVE-2021-28667- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 7.1 High
AV:N/AC:M/Au:N/C:N/I:N/A:C - Weakness
- CWE-835
- Updated
- 2026-11-02
CVE List No score
StackStorm before 3.4.1, in some situations, has an infinite loop that consumes all available memory and disk space. This can occur if Python 3.x is used, the locale is not utf-8, and there is an attempt to log Unicode data (from an action or rule name).
- Record
CVE-2021-28667- Updated
- 2026-11-02
EUVDEUVD-2022-2150 No score
StackStorm before 3.4.1, in some situations, has an infinite loop that consumes all available memory and disk space. This can occur if Python 3.x is used, the locale is not utf-8, and there is an attempt to log Unicode data (from an action or rule name).
- Record
EUVD-2022-2150- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-39mj-fpg2-3jrg
StackStorm st2 Infinite Loop Condition
StackStorm before 3.4.1, in some situations, has an infinite loop that consumes all available memory and disk space. This can occur if Python 3.x is used, the locale is not utf-8, and there is an attempt to log Unicode data (from an action or rule name).
- Record
GHSA-39mj-fpg2-3jrg- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-835
- Updated
- 2026-11-02
OSV
StackStorm before 3.4.1, in some situations, has an infinite loop that consumes all available memory and disk space. This can occur if Python 3.x is used, the locale is not utf-8, and there is an attempt to log Unicode data (from an action or rule name).
- Record
CVE-2021-28667- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVGHSA-39mj-fpg2-3jrg
StackStorm st2 Infinite Loop Condition
StackStorm before 3.4.1, in some situations, has an infinite loop that consumes all available memory and disk space. This can occur if Python 3.x is used, the locale is not utf-8, and there is an attempt to log Unicode data (from an action or rule name).
- Record
GHSA-39mj-fpg2-3jrg- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-835
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-28667 is a high vulnerability (CVSS 7.5) in Stackstorm, published March 18, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.48%, the 84th percentile. No source names a fixed version.