CVE-2026-128121 (GCVE-0-2026-128121)

Vulnerability from cvelistv5 – Published: 2026-11-13 19:44 – Updated: 2026-11-13 21:22
VLAI
Title
SvelteKit: Prerendered paths are interpreted as regular expressions in Vercel route config generated by @sveltejs/adapter-vercel and @sveltejs/adapter-static
Summary
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. Prior to @sveltejs/adapter-vercel 6.3.5 and 7.0.2 and @sveltejs/adapter-static 3.0.11 and 4.0.1, an attacker-influenced link crawled during prerendering could be emitted into the generated Vercel routing configuration without escaping regular-expression metacharacters. The configuration could consequently interpret the path as regular-expression syntax, match unintended application paths, and expose content or behavior outside the intended path. This issue is fixed in @sveltejs/adapter-vercel 6.3.5 and 7.0.2 and @sveltejs/adapter-static 3.0.11 and 4.0.1.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-13 21:22 UTC
CWE
  • CWE-116 - Improper Encoding or Escaping of Output
  • CWE-625 - Permissive Regular Expression
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7868 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
sveltejs kit Affected: < 2.70.4
Affected: >= 3.0.0-next.0, < 3.1.1
guessed Create a notification for this product.
@sveltejs adapter-vercel Affected: < 6.3.5
Affected: >= 7.0.0-next.0, < 7.0.2
guessed Create a notification for this product.
@sveltejs adapter-static Affected: < 3.0.11
Affected: >= 4.0.0-next.0, < 4.0.1
guessed Create a notification for this product.
Show details on NVD website
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}



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