CVE-2026-79671

Ech0 before 4.4.3 contains a server-side request forgery vulnerability in the validateWebhookURL function (webhook_setting_service.go), which only validates literal IP addresses via net.ParseIP() and fails to reject hostnames that DNS-resolve to private or internal IPs (e.g., 169.254.169.254.nip.io). An attacker with admin privileges can create a webhook with such a hostname to bypass validation and cause the server to make requests to internal services, cloud metadata endpoints, and private network resources. The issue is fixed in 4.4.3.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/lin-snow/Ech0/security/advisories/GHSA-r2x7-427f-rq69
https://www.vulncheck.com/advisories/ech0-before-ssrf-via-dns-resolution-bypass
https://github.com/lin-snow/Ech0/security/advisories/GHSA-r2x7-427f-rq69

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-25 12:16

Updated : 2026-08-31 20:50

NVD link : CVE-2026-79671

Mitre link : CVE-2026-79671

CVE.ORG link : CVE-2026-79671

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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