CVE-2026-55376

Heym builds and runs agentic systems and business-process automations on self-hosted infrastructure. Prior to 0.0.40, an authenticated user who can create or edit a workflow with an Agent custom Python tool can bypass the blacklist-based sandbox in backend/app/services/python_tool_executor.py because allowed standard-library modules expose operating-system, process, and filesystem capabilities through public attributes that pass _safe_import() and _validate_code_safety(). The runner then executes the supplied tool with exec(), permitting commands and file operations as the backend application user; self-registration affects reachability, but portal triggering alone does not grant code control. This issue is fixed in 0.0.40.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/heymrun/heym/commit/b36d795c6ea841b8f1b511a0952e274487ee4ef3
https://github.com/heymrun/heym/releases/tag/v0.0.40
https://github.com/heymrun/heym/security/advisories/GHSA-wcgw-9hfw-f6f2
https://github.com/heymrun/heym/security/advisories/GHSA-wcgw-9hfw-f6f2

Configurations

No configuration.

History

16 Oct 2026, 22:17

Type	Values Removed	Values Added
References	~~() https://github.com/heymrun/heym/security/advisories/GHSA-wcgw-9hfw-f6f2 -~~	() https://github.com/heymrun/heym/security/advisories/GHSA-wcgw-9hfw-f6f2 -

13 Oct 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 16:17

Updated : 2026-10-16 22:17

NVD link : CVE-2026-55376

Mitre link : CVE-2026-55376

CVE.ORG link : CVE-2026-55376

JSON object : View

Products Affected

No product.

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CWE-94

Improper Control of Generation of Code ('Code Injection')

CWE-693

Protection Mechanism Failure

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