CVE-2026-41248
CVE-2026-41248 is a critical-severity vulnerability with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-436.
Key facts
- Severity: Critical (CVSS 3.x base score 9.1)
- EPSS exploit prediction: 0% (24th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-25632
- Weakness: CWE-436
- Published:
- Last modified:
Description
Clerk JavaScript is the official JavaScript repository for Clerk authentication. createRouteMatcher in @clerk/nextjs, @clerk/nuxt, and @clerk/astro can be bypassed by certain crafted requests, allowing them to skip middleware gating and reach downstream handlers. This vulnerability is fixed in @clerk/astro 1.5.7, 2.17.10, and 3.0.15; @clerk/nextjs 5.7.6, 6.39.2, and 7.2.1; @clerk/nuxt 1.13.28 and 2.2.2; and @clerk/shared 2.22.1, 3.47.4, anc 4.8.1
Frequently asked questions
- What is CVE-2026-41248?
- Clerk JavaScript is the official JavaScript repository for Clerk authentication. createRouteMatcher in @clerk/nextjs, @clerk/nuxt, and @clerk/astro can be bypassed by certain crafted requests, allowing them to skip middleware gating and reach downstream handlers. This vulnerability is fixed in @clerk/astro 1.5.7, 2.17.10, and 3.0.15; @clerk/nextjs 5.7.6, 6.39.2, and 7.2.1; @clerk/nuxt 1.13.28 and 2.2.2; and @clerk/shared 2.22.1, 3.47.4, anc 4.8.1
- How severe is CVE-2026-41248?
- CVE-2026-41248 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
- Is CVE-2026-41248 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2026-41248?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- Does CVE-2026-41248 have an EU (EUVD) identifier?
- Yes. CVE-2026-41248 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25632.
- When was CVE-2026-41248 published?
- CVE-2026-41248 was published on 2026-04-24 and last updated on 2026-06-17.
References
Other CWE-436 vulnerabilities
- CVE-2023-24813 — Critical (CVSS 10.0): Dompdf is an HTML to PDF converter written in php. Due to the difference in the attribute parser of Dompdf and…
- CVE-2026-8034 — Critical (CVSS 9.8): A server-side request forgery (SSRF) vulnerability was identified in the GitHub Enterprise Server notebook viewer that…
- CVE-2021-45327 — Critical (CVSS 9.8): Gitea before 1.11.2 is affected by Trusting HTTP Permission Methods on the Server Side when referencing the vulnerable…
- CVE-2020-10180 — Critical (CVSS 9.8): The ESET AV parsing engine allows virus-detection bypass via a crafted BZ2 Checksum field in an archive. This affects…
- CVE-2019-19589 — Critical (CVSS 9.8): The Lever PDF Embedder plugin 4.4 for WordPress does not block the distribution of polyglot PDF documents that are…
- CVE-2026-14198 — Critical (CVSS 9.1): @fastify/middie versions 9.1.0 through 9.3.2 decode the encoded slash %2F inside path parameter values before matching…