CVSS 4.0
5.1 mediumCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:NCVE-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.
Severity
CVSS 3.1
5.5 mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N- EPSS
- 0.3% chance of exploitation in the next 30 days; higher than 24% of CVEs (scores of 2026-10-31)
- CWE
- CWE-918
- Published
- Modified
- Record from
- the NVD, synced
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-r2x7-427f-rq69 | Go | github.com/lin-snow/ech0 | <4.4.3 | 4.4.3 |
| GO-2026-5603 | Go | github.com/lin-snow/ech0 | all versions | no fix published |