CVE-2026-100864

heym before 0.0.91 contains a sandbox escape vulnerability in the expression engine's DotList map/filter and fallback resolver that allows authenticated users to execute arbitrary Python code. Attackers can craft workflow expressions using dunder attribute access through item expressions or the fallback resolver to access os.system and execute commands as the backend process.

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/security/advisories/GHSA-87x2-9jwx-7gh4
https://www.vulncheck.com/advisories/heym-before-0.0.91-remote-code-execution-via-expression-engine
https://github.com/heymrun/heym/security/advisories/GHSA-87x2-9jwx-7gh4

Configurations

No configuration.

History

28 Sep 2026, 17:17

Type	Values Removed	Values Added
References	~~() https://github.com/heymrun/heym/security/advisories/GHSA-87x2-9jwx-7gh4 -~~	() https://github.com/heymrun/heym/security/advisories/GHSA-87x2-9jwx-7gh4 -

27 Sep 2026, 02:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-27 02:17

Updated : 2026-09-28 20:57

NVD link : CVE-2026-100864

Mitre link : CVE-2026-100864

CVE.ORG link : CVE-2026-100864

JSON object : View

Products Affected

No product.

CWE

CWE-94

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

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