CVE-2026-33638

Ech0 authenticated user-list exposed data via public `/api/allusers` endpoint

MEDIUM
5.3
CVSS Score
Published: March 26, 2026 at 08:52 PM UTC
Updated: June 17, 2026 at 10:37 AM UTC
2 products affected across 2 vendorsECH0Ech0

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.5%
SSVC
PoC

Description

Ech0 is an open-source, self-hosted publishing platform for personal idea sharing. Prior to version 4.2.0, `GET /api/allusers` is mounted as a public endpoint and returns user records without authentication. This allows remote unauthenticated user enumeration and exposure of user profile metadata. A fix is available in v4.2.0.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 4.2.0
v < 4.2.0
Affected range stops below 4.2.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

x_refsource_CONFIRMVendor Advisory
Source: cverecord
https://github.com/lin-snow/Ech0/security/advisories/GHSA-m983-7426-5hrj
x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/lin-snow/Ech0/releases/tag/v4.2.0

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-862

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