{"id":"CVE-2025-53548","aliases":["GHSA-9mp4-77wg-rwx9"],"url":"https://o3.security/vulnerability/CVE-2025-53548","summary":"@clerk/backend Performs Insufficient Verification of Data Authenticity","details":"### Impact\n\nApplications that use the `verifyWebhook()` helper to verify incoming Clerk webhooks are susceptible to accepting improperly signed webhook events.\n\n### Patches\n\n* `@clerk/backend`: the helper has been patched as of `2.4.0`\n* `@clerk/astro`: the helper has been patched as of `2.10.2`\n* `@clerk/express`: the helper has been patched as of `1.7.4`\n* `@clerk/fastify`: the helper has been patched as of `2.4.4`\n* `@clerk/nextjs`: the helper has been patched as of `6.23.3`\n* `@clerk/nuxt`: the helper has been patched as of `1.7.5`\n* `@clerk/react-router`: the helper has been patched as of `1.6.4`\n* `@clerk/remix`: the helper has been patched as of `4.8.5`\n* `@clerk/tanstack-react-start`: the helper has been patched as of `0.18.3`\n\n### Resolution\n\nThe issue was resolved in **`@clerk/backend` `2.4.0`** by:\n\n* Properly parsing the webhook request's signatures and comparing them against the signature generated from the received event\n\n### Workarounds\n\nIf unable to upgrade, developers can workaround this issue by verifying webhooks manually, per [this documentation](https://clerk.com/docs/webhooks/overview#protect-your-webhooks-from-abuse).","published":"2025-07-09T17:12:10.483Z","modified":"2026-10-28T02:31:00.718789353Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"@clerk/backend","fixedVersion":"2.4.0"},{"ecosystem":"npm","name":"@clerk/astro","fixedVersion":"2.10.2"},{"ecosystem":"npm","name":"@clerk/express","fixedVersion":"1.7.4"},{"ecosystem":"npm","name":"@clerk/fastify","fixedVersion":"2.4.4"},{"ecosystem":"npm","name":"@clerk/nextjs","fixedVersion":"6.23.3"},{"ecosystem":"npm","name":"@clerk/nuxt","fixedVersion":"1.7.5"},{"ecosystem":"npm","name":"@clerk/react-router","fixedVersion":"1.6.4"},{"ecosystem":"npm","name":"@clerk/remix","fixedVersion":"4.8.5"},{"ecosystem":"npm","name":"@clerk/tanstack-react-start","fixedVersion":"0.18.3"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/53xxx/CVE-2025-53548.json"},{"type":"ADVISORY","url":"https://github.com/clerk/javascript/security/advisories/GHSA-9mp4-77wg-rwx9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-53548"},{"type":"PACKAGE","url":"https://github.com/clerk/javascript"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T02:31:00.718789353Z"}}