{
    "document": {
        "category": "csaf_base",
        "csaf_version": "2.0",
        "distribution": {
            "tlp": {
                "label": "WHITE"
            }
        },
        "lang": "en",
        "notes": [
            {
                "category": "legal_disclaimer",
                "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this portal to enhance access to its information and vulnerabilities. The use of this information is subject to the following terms and conditions:\n\nThe vulnerabilities disclosed in this portal are gathered by NCSC-NL from a variety of open sources, which the user can retrieve from other platforms. NCSC-NL makes every reasonable effort to ensure that the content of this portal is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or real-time keeping up-to-date. NCSC-NL does not control nor guarantee the accuracy, relevance, timeliness or completeness of information obtained from these external sources. The vulnerabilities disclosed in this portal are intended solely for the convenience of professional parties to take appropriate measures to manage the risks posed to the cybersecurity. No rights can be derived from the information provided therein.\n\nNCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of the vulnerabilities disclosed in this portal. This includes damage resulting from the inaccuracy of incompleteness of the information contained in it.\nThe information on this page is subject to Dutch law. All disputes related to or arising from the use of this portal regarding the disclosure of vulnerabilities will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings."
            }
        ],
        "publisher": {
            "category": "coordinator",
            "contact_details": "cert@ncsc.nl",
            "name": "National Cyber Security Centre",
            "namespace": "https://www.ncsc.nl/"
        },
        "title": "CVE-2026-34076",
        "tracking": {
            "current_release_date": "2026-04-02T14:59:47.532858Z",
            "generator": {
                "date": "2026-02-17T15:00:00Z",
                "engine": {
                    "name": "V.E.L.M.A",
                    "version": "1.7"
                }
            },
            "id": "CVE-2026-34076",
            "initial_release_date": "2026-03-27T21:35:09.292494Z",
            "revision_history": [
                {
                    "date": "2026-03-27T21:35:09.292494Z",
                    "number": "1",
                    "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (2).| CWES updated (1)."
                },
                {
                    "date": "2026-03-27T21:35:19.286804Z",
                    "number": "2",
                    "summary": "NCSC Score created."
                },
                {
                    "date": "2026-04-01T17:39:16.066100Z",
                    "number": "3",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products created (4).| References created (1).| CWES updated (1)."
                },
                {
                    "date": "2026-04-01T17:39:18.358183Z",
                    "number": "4",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-04-01T18:39:56.282933Z",
                    "number": "5",
                    "summary": "Unknown change."
                },
                {
                    "date": "2026-04-01T23:04:52.135138Z",
                    "number": "6",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (1).| CWES updated (1)."
                },
                {
                    "date": "2026-04-01T23:04:54.649408Z",
                    "number": "7",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-04-02T14:59:43.054473Z",
                    "number": "8",
                    "summary": "Source connected.| CVE status created. (valid)| EPSS created."
                },
                {
                    "date": "2026-04-02T14:59:45.648590Z",
                    "number": "9",
                    "summary": "NCSC Score updated."
                }
            ],
            "status": "interim",
            "version": "9"
        }
    },
    "product_tree": {
        "branches": [
            {
                "branches": [
                    {
                        "branches": [
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/clerk/backend>=3.0.0|<3.2.3",
                                "product": {
                                    "name": "vers:unknown/clerk/backend>=3.0.0|<3.2.3",
                                    "product_id": "CSAFPID-5980803"
                                }
                            },
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/clerk/express>=2.0.0|<2.0.7",
                                "product": {
                                    "name": "vers:unknown/clerk/express>=2.0.0|<2.0.7",
                                    "product_id": "CSAFPID-5980802"
                                }
                            },
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/clerk/fastify>=3.1.0|<3.1.5",
                                "product": {
                                    "name": "vers:unknown/clerk/fastify>=3.1.0|<3.1.5",
                                    "product_id": "CSAFPID-5980804"
                                }
                            },
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/clerk/hono>=0.1.0|<0.1.5",
                                "product": {
                                    "name": "vers:unknown/clerk/hono>=0.1.0|<0.1.5",
                                    "product_id": "CSAFPID-5980801"
                                }
                            }
                        ],
                        "category": "product_name",
                        "name": "javascript"
                    }
                ],
                "category": "vendor",
                "name": "Clerk"
            }
        ]
    },
    "vulnerabilities": [
        {
            "cve": "CVE-2026-34076",
            "cwe": {
                "id": "CWE-918",
                "name": "Server-Side Request Forgery (SSRF)"
            },
            "notes": [
                {
                    "category": "description",
                    "text": "## Summary\n\nThe `clerkFrontendApiProxy` function in `@clerk/backend` is vulnerable to Server-Side Request Forgery (SSRF). An unauthenticated attacker can craft a request path that causes the proxy to send the application's `Clerk-Secret-Key` to an attacker-controlled server.\n\n## Affected packages\n\nOnly applications that have opted into the `frontendApiProxy` feature are affected. This feature is not enabled by default. **Users of `@clerk/nextjs` are not affected** due to how the framework handles repeated `/` in request paths.\n\n| Package | Affected versions | Fixed version |\n|---|---|---|\n| `@clerk/backend` | `>= 3.0.0, <= 3.2.2` | `3.2.3` |\n| `@clerk/express` | `>= 2.0.0, <= 2.0.6` | `2.0.7` |\n| `@clerk/hono` | `>= 0.1.0, <= 0.1.4` | `0.1.5` |\n| `@clerk/fastify` | `>= 3.1.0, <= 3.1.4` | `3.1.5` |\n\nSearch your codebase for the `frontendApiProxy` option. If none of the patterns below appear in your code, you are not affected.\n\n**@clerk/express**\n```ts\napp.use(clerkMiddleware({ frontendApiProxy: { enabled: true } }));\n```\n\n**@clerk/hono**\n```ts\napp.use('*', clerkMiddleware({ frontendApiProxy: { enabled: true } }));\n```\n\n**@clerk/fastify**\n```ts\nfastify.register(clerkPlugin, { frontendApiProxy: { enabled: true } });\n```\n\n**@clerk/backend**\n```ts\nimport { clerkFrontendApiProxy } from '@clerk/backend/proxy';\n```\n\nA quick way to check across your entire project:\n\n```sh\ngrep -r \"frontendApiProxy\\|clerkFrontendApiProxy\" .\n```\n\nIf there are no matches, you are not using this feature.\n\n\n## Recommended actions\n\nClerk's internal logs show no evidence of users utilizing the built-in proxy with the impacted versions. Despite that, if you are on an impacted version and use the built-in proxy we recommend upgrading and rotating your Clerk Secret Key immediately.\n\n1. **Upgrade** to the patched version of `@clerk/backend` (and `@clerk/express`, `@clerk/hono`, etc.)\n2. **Rotate your Clerk Secret Key** after upgrading - if an attacker exploited this vulnerability, they may have captured your key. Rotate it in the [Clerk Dashboard](https://dashboard.clerk.com) under **API Keys**.  You should deploy your application with the updated key before revoking the existing key.\n3. **Audit access logs** for requests to your proxy endpoint (`/__clerk/` by default) containing double slashes in the path.\n\n\n\n## Credit\n\nDiscovered during an internal code audit.",
                    "title": "github - https://api.github.com/advisories/GHSA-gjxx-92w9-8v8f"
                },
                {
                    "category": "description",
                    "text": "Clerk JavaScript is the official JavaScript repository for Clerk authentication. In @clerk/hono from versions 0.1.0 to before 0.1.5, @clerk/express from versions 2.0.0 to before 2.0.7, @clerk/backend from versions 3.0.0 to before 3.2.3, and @clerk/fastify from versions 3.1.0 to before 3.1.5, the clerkFrontendApiProxy function in @clerk/backend is vulnerable to Server-Side Request Forgery (SSRF). An unauthenticated attacker can craft a request path that causes the proxy to send the application's Clerk-Secret-Key to an attacker-controlled server. This issue has been patched in @clerk/hono version 0.1.5, @clerk/express version 2.0.7, @clerk/backend version 3.2.3, and @clerk/fastify version 3.1.5.",
                    "title": "cveprojectv5 - https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34076.json"
                },
                {
                    "category": "description",
                    "text": "Clerk JavaScript is the official JavaScript repository for Clerk authentication. In @clerk/hono from versions 0.1.0 to before 0.1.5, @clerk/express from versions 2.0.0 to before 2.0.7, @clerk/backend from versions 3.0.0 to before 3.2.3, and @clerk/fastify from versions 3.1.0 to before 3.1.5, the clerkFrontendApiProxy function in @clerk/backend is vulnerable to Server-Side Request Forgery (SSRF). An unauthenticated attacker can craft a request path that causes the proxy to send the application's Clerk-Secret-Key to an attacker-controlled server. This issue has been patched in @clerk/hono version 0.1.5, @clerk/express version 2.0.7, @clerk/backend version 3.2.3, and @clerk/fastify version 3.1.5.",
                    "title": "nvd - https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-34076"
                },
                {
                    "category": "other",
                    "text": "0.00038",
                    "title": "EPSS"
                },
                {
                    "category": "other",
                    "text": "4.0",
                    "title": "NCSC Score"
                },
                {
                    "category": "other",
                    "text": "There is cwe data available from source Nvd, Is related to (a version of) an uncommon product",
                    "title": "NCSC Score top decreasing factors"
                }
            ],
            "product_status": {
                "known_affected": [
                    "CSAFPID-5980801",
                    "CSAFPID-5980802",
                    "CSAFPID-5980803",
                    "CSAFPID-5980804"
                ]
            },
            "references": [
                {
                    "category": "external",
                    "summary": "Source - github",
                    "url": "https://api.github.com/advisories/GHSA-gjxx-92w9-8v8f"
                },
                {
                    "category": "external",
                    "summary": "Source - cveprojectv5",
                    "url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34076.json"
                },
                {
                    "category": "external",
                    "summary": "Source - nvd",
                    "url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-34076"
                },
                {
                    "category": "external",
                    "summary": "Source - first",
                    "url": "https://api.first.org/data/v1/epss?limit=10000&offset=0"
                },
                {
                    "category": "external",
                    "summary": "Reference - cveprojectv5; github; nvd",
                    "url": "https://github.com/clerk/javascript/security/advisories/GHSA-gjxx-92w9-8v8f"
                },
                {
                    "category": "external",
                    "summary": "Reference - github",
                    "url": "https://github.com/advisories/GHSA-gjxx-92w9-8v8f"
                }
            ],
            "scores": [
                {
                    "cvss_v3": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
                        "baseScore": 7.4,
                        "baseSeverity": "HIGH"
                    },
                    "products": [
                        "CSAFPID-5980801",
                        "CSAFPID-5980802",
                        "CSAFPID-5980803",
                        "CSAFPID-5980804"
                    ]
                }
            ],
            "title": "CVE-2026-34076"
        }
    ]
}