GHSA-vh4h-fvqf-q9wv: Duplicate Advisory @cloudflare/workers-oauth-provider PKCE Bypass Vulnerability
MODERATEGHSA-vh4h-fvqf-q9wv is a MODERATE @cloudflare/workers-oauth-provider pkce bypass vulnerability (CWE-287: Improper Authentication) affecting Duplicate Advisory libraries in the npm ecosystem. The issue involves @cloudflare/workers-oauth-provider pkce bypass via downgrade attack. Remediation is available by upgrading affected packages to version 0.0.5.
GHSA-vh4h-fvqf-q9wv at a Glance
How to Fix GHSA-vh4h-fvqf-q9wv
To remediate this vulnerability, upgrade all affected Duplicate Advisory dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
npm install @cloudflare/workers-oauth-provider@0.0.5Run the following command in your project directory to verify that all resolved dependencies use the patched release:
npm ls @cloudflare/workers-oauth-providerHow to Check if You Are Affected
To determine whether your Node.js application is affected by GHSA-vh4h-fvqf-q9wv, inspect your project dependencies using npm:
npm ls @cloudflare/workers-oauth-providerAnalyze the terminal output to locate any version of Duplicate Advisory in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.0.5), your application is affected.
Note: The npm ls @cloudflare/workers-oauth-provider command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-287: Improper Authentication, where when an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. In Duplicate Advisory, 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
GHSA-vh4h-fvqf-q9wv Affected Duplicate Advisory Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
@cloudflare/workers-oauth-provider
|
npm |
< 0.0.5
|
0.0.5
|
References
Frequently Asked Questions
What is GHSA-vh4h-fvqf-q9wv?
Which Duplicate Advisory versions are affected?
What version fixes GHSA-vh4h-fvqf-q9wv?
Is @cloudflare/workers-oauth-provider affected?
What CWE is associated with GHSA-vh4h-fvqf-q9wv?
How can I check npm dependencies for GHSA-vh4h-fvqf-q9wv?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-vh4h-fvqf-q9wv",
"modified" : "2025-05-01T17:01:34Z",
"published" : "2025-05-01T03:31:17Z",
"withdrawn" : "2025-05-01T17:01:33Z",
"aliases" : [ ],
"summary" : "Duplicate Advisory: @cloudflare/workers-oauth-provider PKCE bypass via downgrade attack",
"details" : "# Duplicate Advisory\nThis advisory has been withdrawn because it is a duplicate of GHSA-qgp8-v765-qxx9. This link is maintained to preserve external references.\n\n# Original Description\nPKCE was implemented in the OAuth implementation in workers-oauth-provider that is part of MCP framework https://github.com/cloudflare/workers-mcp . However, it was found that an attacker could cause the check to be skipped.\n\n\nFixed in:\n\n \n\n https://github.com/cloudflare/workers-oauth-provider/pull/27 https://github.com/cloudflare/workers-oauth-provider/pull/27 \n\n\nImpact: \n\nPKCE is a defense-in-depth mechanism against certain kinds of attacks and was an optional extension in OAuth 2.0 which became required in the OAuth 2.1 draft. (Note that the MCP specification requires OAuth 2.1.). This bug completely bypasses PKCE protection.",
"severity" : [ {
"type" : "CVSS_V4",
"score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "npm",
"name" : "@cloudflare/workers-oauth-provider"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "0.0.5"
} ]
} ]
} ],
"references" : [ {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-4144"
}, {
"type" : "WEB",
"url" : "https://github.com/cloudflare/workers-oauth-provider/pull/27"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-287" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2025-05-01T17:01:33Z",
"nvd_published_at" : "2025-05-01T01:15:54Z"
}
}