CVE-2026-33638: Github.com/lin snow/ech0 Ech0 Authenticated User-list Exposed Data Vulnerability
MODERATECVE-2026-33638 is a MODERATE (CVSS 5.3) ech0 authenticated user-list exposed data vulnerability (CWE-862: Missing Authorization) affecting Github.com/lin snow/ech0 libraries in the Go ecosystem. The issue involves ech0 authenticated user-list exposed data via public `/api/allusers` endpoint. Remediation is available by upgrading affected packages to version 1.4.8-0.20260322121226-acbf1fd71011.
CVE-2026-33638 at a Glance
Security Impact
CVSS: 5.3
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N).
How to Fix CVE-2026-33638
To remediate this vulnerability, upgrade all affected Github.com/lin snow/ech0 dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade github.com/lin-snow/ech0 to 1.4.8-0.20260322121226-acbf1fd71011Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/lin-snow/ech0How to Check if You Are Affected
To determine whether your application is affected by CVE-2026-33638, inspect your project dependencies for Github.com/lin snow/ech0:
inspect dependencies for github.com/lin-snow/ech0Analyze the terminal output to locate any version of Github.com/lin snow/ech0 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.4.8-0.20260322121226-acbf1fd71011), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-862: Missing Authorization, where the product does not perform an authorization check when an actor attempts to access a resource or perform an action. In Github.com/lin snow/ech0, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2026-33638 Affected Github.com/lin snow/ech0 Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/lin-snow/ech0
|
Go |
< 1.4.8-0.20260322121226-acbf1fd71011
|
1.4.8-0.20260322121226-acbf1fd71011
|
References
Frequently Asked Questions
What is CVE-2026-33638?
Which Github.com/lin snow/ech0 versions are affected?
What version fixes CVE-2026-33638?
Is github.com/lin-snow/ech0 affected?
What is the CVSS score of CVE-2026-33638?
What CWE is associated with CVE-2026-33638?
How can I check Go dependencies for CVE-2026-33638?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-m983-7426-5hrj",
"modified" : "2026-03-30T20:27:17Z",
"published" : "2026-03-24T22:25:03Z",
"aliases" : [ "CVE-2026-33638" ],
"summary" : "Ech0 authenticated user-list exposed data via public `/api/allusers` endpoint ",
"details" : "### Summary\nA public access-control flaw allows unauthenticated users to retrieve the full user list from `GET /api/allusers`. This exposes user profile metadata to anyone who can reach the application and enables remote user enumeration.\n\n### Details\nThe vulnerable route is registered as a public endpoint:\n\n- `internal/router/user.go:17`\n - `appRouterGroup.PublicRouterGroup.GET(\"/allusers\", h.UserHandler.GetAllUsers())`\n\nHowever, the handler appears to have been intended as an authenticated endpoint:\n\n- `internal/handler/user/user.go:177-185`\n - API annotations indicate an authentication requirement via `@Security ApiKeyAuth`\n\nThis creates a mismatch between the documented security model and the actual routing configuration. As a result, requests to `GET /api/allusers` succeed without authentication and return user records, including profile metadata such as usernames, email addresses, role-related flags, avatar values, and locale information.\n\nA negative control against another endpoint that correctly requires authentication further supports that this exposure is unintended: `GET /api/user` returns `401 Unauthorized` when no token is supplied, while `GET /api/allusers` remains publicly accessible.\n\n### Impact\n- **Type:** Access control bypass / unauthenticated data exposure\n- **Who is impacted:** Any deployment exposing the API to untrusted networks, and all users whose profile metadata is returned by the endpoint\n- **Security impact:** Enables remote user enumeration and disclosure of user profile metadata, which may facilitate account reconnaissance, phishing, and targeted credential attacks\n- **Attack preconditions:** None beyond network access to the affected API endpoint",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/lin-snow/ech0"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "1.4.8-0.20260322121226-acbf1fd71011"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/lin-snow/Ech0/security/advisories/GHSA-m983-7426-5hrj"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-33638"
}, {
"type" : "WEB",
"url" : "https://github.com/lin-snow/Ech0/commit/acbf1fd71011e6b9e1e6a911128056a19862f681"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/lin-snow/Ech0"
}, {
"type" : "WEB",
"url" : "https://github.com/lin-snow/Ech0/releases/tag/v4.2.0"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-862" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2026-03-24T22:25:03Z",
"nvd_published_at" : "2026-03-26T21:17:07Z"
}
}