CVE-2026-128122

Description

SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From version 4.7.0 until versions 7.2.10 and 8.0.2, @sveltejs/adapter-cloudflare allowed an attacker-influenced link crawled during prerendering to place whitespace, control characters, wildcards, or placeholders into a prerendered redirect path. The adapter wrote those paths into the Cloudflare _redirects output without output-context validation, allowing a path to create unintended routing rules that could redirect or expose requests beyond the intended prerendered route. This issue is fixed in 7.2.10 and 8.0.2.

References

• https://github.com/sveltejs/kit/commit/0a2e58cbccdd46cac20aa5af4e2edf17e0da11dd
• https://github.com/sveltejs/kit/commit/679e0d84ea9951bb4f1e458a599066b5a451b08a
• https://github.com/sveltejs/kit/pull/17620
• https://github.com/sveltejs/kit/releases/tag/@sveltejs/adapter-cloudflare@7.2.10
• https://github.com/sveltejs/kit/releases/tag/@sveltejs/adapter-cloudflare@8.0.2