CVE-2026-100858

heym before 0.0.109 contains a server-side request forgery vulnerability in the Slack, Discord, and Crawler workflow nodes. These nodes issue HTTP requests to URLs taken from user-created credentials (webhook_url / flaresolverr_url) using an unguarded HTTP client, bypassing the SSRF egress guard that already protects the HTTP, WebSocket, and MCP nodes; the credential API validates only that the URL is non-empty. Any registered user can create a credential pointing at an internal address and execute a workflow, causing the backend to reach loopback, private, link-local, or cloud-metadata endpoints and return the full response body in the node output (non-blind SSRF).

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/heymrun/heym/security/advisories/GHSA-39j3-6x3x-8rcr
https://www.vulncheck.com/advisories/heym-before-0.0.109-server-side-request-forgery-via-workflow-nodes
https://github.com/heymrun/heym/security/advisories/GHSA-39j3-6x3x-8rcr

Configurations

No configuration.

History

30 Sep 2026, 16:17

Type	Values Removed	Values Added
References	~~() https://github.com/heymrun/heym/security/advisories/GHSA-39j3-6x3x-8rcr -~~	() https://github.com/heymrun/heym/security/advisories/GHSA-39j3-6x3x-8rcr -

27 Sep 2026, 02:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-27 02:17

Updated : 2026-09-30 16:17

NVD link : CVE-2026-100858

Mitre link : CVE-2026-100858

CVE.ORG link : CVE-2026-100858

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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