7.5
HIGH CVSS 3.1
CVE-2026-35036
Ech0 Affected by Unauthenticated Server-Side Request Forgery in Website Preview Feature
Description

Ech0 is an open-source, self-hosted publishing platform for personal idea sharing. Prior to 4.2.8, Ech0 implements link preview (editor fetches a page title) through GET /api/website/title. That is legitimate product behavior, but the implementation is unsafe: the route is unauthenticated, accepts a fully attacker-controlled URL, performs a server-side GET, reads the entire response body into memory (io.ReadAll). There is no host allowlist, no SSRF filter, and InsecureSkipVerify: true on the outbound client. Anyone who can reach the instance can force the Ech0 server to open HTTP/HTTPS URLs of their choice as seen from the server’s network position (Docker bridge, VPC, localhost from the process view). This vulnerability is fixed in 4.2.8.

INFO

Published Date :

April 6, 2026, 5:17 p.m.

Last Modified :

April 6, 2026, 5:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-35036 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update Ech0 to version 4.2.8 or later to patch the server-side request forgery vulnerability.
  • Update Ech0 to version 4.2.8 or later.
  • Verify server-side request forgery is mitigated.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-35036.

URL Resource
https://github.com/lin-snow/Ech0/security/advisories/GHSA-wc4h-2348-jc3p
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-35036 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-35036 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-35036 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-35036 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Apr. 06, 2026

    Action Type Old Value New Value
    Added Description Ech0 is an open-source, self-hosted publishing platform for personal idea sharing. Prior to 4.2.8, Ech0 implements link preview (editor fetches a page title) through GET /api/website/title. That is legitimate product behavior, but the implementation is unsafe: the route is unauthenticated, accepts a fully attacker-controlled URL, performs a server-side GET, reads the entire response body into memory (io.ReadAll). There is no host allowlist, no SSRF filter, and InsecureSkipVerify: true on the outbound client. Anyone who can reach the instance can force the Ech0 server to open HTTP/HTTPS URLs of their choice as seen from the server’s network position (Docker bridge, VPC, localhost from the process view). This vulnerability is fixed in 4.2.8.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
    Added CWE CWE-918
    Added Reference https://github.com/lin-snow/Ech0/security/advisories/GHSA-wc4h-2348-jc3p
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.