Is there a public exploit for CVE-2026-128121?

No public exploit for CVE-2026-128121 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-128121?

CVE-2026-128121 scores CVSS 5.9 (v3.1), rated medium.

What does CVE-2026-128121 affect?

CVE-2026-128121 affects @sveltejs/adapter-vercel, @sveltejs/adapter-static.

5.9 Medium

SvelteKit: Prerendered paths are interpreted as regular expressions in Vercel route config generated by @sveltejs/adapter-vercel and @sveltejs/adapter-static

CVE-2026-128121

If an attacker could influence a link that was crawled during the prerender phase, that link could later be interpreted as a regex in the Vercel routing configuration.

Assessment

CVSS: 5.9 (v3.1)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 13 November 2026
Last updated: 13 November 2026
Affected: @sveltejs/adapter-vercel · @sveltejs/adapter-static
Weakness: CWE-116, CWE-625

CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

At the source

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