What is CVE-2026-35037?

CVE-2026-35037 is a high-severity vulnerability in Ech0, classified under Server-Side Request Forgery (SSRF). CVSS score: 7.2/10. Published 2026-04-06.

How severe is CVE-2026-35037?

High severity. CVSS v3 base score is 7.2 out of 10.

Is CVE-2026-35037 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

SSRF in Ech0

CVE-2026-35037

Ech0 is an open-source, self-hosted publishing platform for personal idea sharing. Prior to 4.2.8, the GET /api/website/title endpoint accepts an arbitrary URL via the website_url query parameter and makes a server-side HTTP request to it without any validation of the target host or IP address. The endpoint requires no authentication. An attacker can use this to reach internal network services, cloud metadata endpoints (169.254.169.254), and localhost-bound services, with partial response data exfiltrated via the HTML <title> tag extraction This vulnerability is fixed in 4.2.8.

Vulnerability class: SSRF (Server-Side Request Forgery)

EPSS: 0.003 (21.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N.

Affected products

Ech0
Lin-snow Ech0 — versions < 4.2.8

Weakness classification (CWE)

CWE-918 — Server-Side Request Forgery (SSRF)

Public proof-of-concept exploits

fineman999/POC_CVE-2026-35037

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Mitigation, Vendor Advisory)

Frequently asked questions

What is CVE-2026-35037?: CVE-2026-35037 is a high-severity vulnerability in Ech0, classified under Server-Side Request Forgery (SSRF). CVSS score: 7.2/10. Published 2026-04-06.
How severe is CVE-2026-35037?: High severity. CVSS v3 base score is 7.2 out of 10.
Is CVE-2026-35037 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.