CVE-2026-35580

Emissary is a P2P based data-driven workflow engine. Prior to 8.39.0, GitHub Actions workflow files contained shell injection points where user-controlled workflow_dispatch inputs were interpolated directly into shell commands via ${{ }} expression syntax. An attacker with repository write access could inject arbitrary shell commands, leading to repository poisoning and supply chain compromise affecting all downstream users. This vulnerability is fixed in 8.39.0.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.3 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/NationalSecurityAgency/emissary/pull/1286	Patch
https://github.com/NationalSecurityAgency/emissary/pull/1288	Patch
https://github.com/NationalSecurityAgency/emissary/security/advisories/GHSA-3g6g-gq4r-xjm9	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nsa:emissary:*:*:*:*:*:*:*:*

History

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Emissary es un motor de flujo de trabajo impulsado por datos basado en P2P. Antes de 8.39.0, los archivos de flujo de trabajo de GitHub Actions contenían puntos de inyección de shell donde las entradas “workflow_dispatch” controladas por el usuario se interpolaban directamente en comandos de shell a través de la sintaxis de expresión ${{ }}. Un atacante con acceso de escritura al repositorio podría inyectar comandos de shell arbitrarios, lo que lleva al envenenamiento del repositorio y al compromiso de la cadena de suministro que afecta a todos los usuarios posteriores. Esta vulnerabilidad está corregida en 8.39.0.

Information

Published : 2026-04-07 17:16

Updated : 2026-10-26 21:10

NVD link : CVE-2026-35580

Mitre link : CVE-2026-35580

CVE.ORG link : CVE-2026-35580

JSON object : View

Products Affected

nsa

emissary

CWE

CWE-77

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

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