CVE-2026-35036 | Ech0 Affected by Unauthenticated Server-Side Request Forgery in Website Preview Feature

Exp

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.

Published: 2026-04-06 Last update: 2026-04-14 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-35036 is rated Exploit Available (52/100): CVSS High severity, with low exploitation likelihood (EPSS 0.07%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-35036

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-35036

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-18 0.03% 0.07% +0.03%
2 2026-04-07 — 0.03% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-35036

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-35036

GitHub Security Advisory for CVE-2026-35036

GHSA-wc4h-2348-jc3p · Severity: high · Ecosystem: go — Ech0 has Unauthenticated Server-Side Request Forgery in Website Preview Feature

Affected software / configurations for CVE-2026-35036

Vendor Product Version Raw CPE
ech0 ech0 < 4.2.8 cpe:2.3:a:ech0:ech0:*:*:*:*:*:*:*:*

References for CVE-2026-35036

cvelogic Threat Intelligence