High severity · published Sep 27, 2026
CVE-2026-100865
Heym before 0.0.53 Remote Code Execution via eval() Sandbox Escape
8.8
CVSS
0.4%
EPSS
No
On KEV
Description
Heym before 0.0.53 evaluates workflow condition expressions using Python's eval() with insufficient sandboxing in the workflow executor service. Authenticated users can edit workflow condition nodes or import malicious templates to execute arbitrary Python and OS commands as the backend process user.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 34% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HE
heym · heymrun
before 0.0.53 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-100865
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-100865
vendor-advisory
https://github.com/heymrun/heym/security/advisories/GHSA-pm6h-x3h5-j38h
patch
https://github.com/heymrun/heym/commit/341d1012367cd74f85c617e1c98dd49e3fcb5e83
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