Answer in brief
CVE-2026-128121 records a Medium severity (CVSS 5.9) vulnerability in SvelteKit: Prerendered paths are interpreted as regular expressions in Vercel route config generated by @sveltejs/adapter-vercel and @sveltejs/adapter-static. The current sources do not mark it as known exploited. The current feed maps @sveltejs/adapter-static (generic), @sveltejs/adapter-vercel (generic), sveltejs/kit (generic), @sveltejs/adapter-static (npm) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps @sveltejs/adapter-static (generic), @sveltejs/adapter-vercel (generic), sveltejs/kit (generic), @sveltejs/adapter-static (npm) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| @sveltejs/adapter-staticgeneric | <3.0.11 || >=4.0.0-next.0 <4.0.1 | 3.0.11, 4.0.1 |
| @sveltejs/adapter-vercelgeneric | <6.3.5 || >=7.0.0-next.0 <7.0.2 | 6.3.5, 7.0.2 |
| sveltejs/kitgeneric | <2.70.4 || >=3.0.0-next.0 <3.1.1 | 2.70.4, 3.1.1 |
| @sveltejs/adapter-staticnpm | >=4.0.0-next.0,<4.0.1 | 4.0.1 |
| @sveltejs/adapter-staticnpm | <3.0.11 | 3.0.11 |
| @sveltejs/adapter-staticnpm | >=4.0.0-next.0,<4.0.1 | 4.0.1 |
| @sveltejs/adapter-staticnpm | <3.0.11 | 3.0.11 |
| @sveltejs/adapter-vercelnpm | <6.3.5 | 6.3.5 |
| @sveltejs/adapter-vercelnpm | >=7.0.0-next.0,<7.0.2 | 7.0.2 |
| @sveltejs/adapter-vercelnpm | <6.3.5 | 6.3.5 |
| @sveltejs/adapter-vercelnpm | >=7.0.0-next.0,<7.0.2 | 7.0.2 |
Published upstream
Nov 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 13, 2026
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.
Quoted source text, attributed separately from HOL analysis.