CVE-2026-54442
Received
Received - Intake
Emissary Workflow Engine Protocol-Relative URL Validation Bypass
Vulnerability report for CVE-2026-54442, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-05
Last updated on: 2026-11-05
Assigner: GitHub, Inc.
Description
Description
Emissary is a P2P based data-driven workflow engine. Prior to 8.51.0, the VALID_LINK validation in src/main/java/emissary/server/mvc/NavAction.java accepts protocol-relative URLs when processing configured navigation links. Browser URL normalization can interpret these accepted strings as external origins. The authoritative advisory attributes open redirect, server-side request forgery, and cloud metadata access to this bypass, but it identifies neither the server-side dereference path nor how navigation-link processing reaches that path. This issue is fixed in version 8.51.0.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| NationalSecurityAgency | emissary | < 8.51.0 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-918 | The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. |