Ech0 Affected by Unauthenticated Server-Side Request Forgery in Website Preview Feature
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-35036
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 4 Nov 2026, 03:52 UTC · Revision 1
Source evidence
Ech0 Affected by Unauthenticated Server-Side Request Forgery in Website Preview Feature
core-osv · Original sourcePublished 6 Apr 2026, 16:55 UTC
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.
osv:CVE-2026-35036
Complete source record
{
"id": "4bc34b4dd44163198eedd24ae1209a48377b40ed39224bd2ad39c56e8b9c7fc6",
"url": "https://osv.dev/vulnerability/CVE-2026-35036",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Ech0 Affected by Unauthenticated Server-Side Request Forgery in Website Preview Feature",
"summary": "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.",
"evidence": "osv:CVE-2026-35036",
"products": [],
"severity": "high",
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"GO-2026-5704"
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}
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"modified": "2026-10-28T02:30:32.837355368Z",
"provider": "osv",
"references": [
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"https://github.com/lin-snow/Ech0/security/advisories/GHSA-wc4h-2348-jc3p",
"https://nvd.nist.gov/vuln/detail/CVE-2026-35036"
],
"provider_metadata": {
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"evidence": "/id"
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"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 500125,
"published_at": "2026-04-06T16:55:47.544+00:00"
}