CVE-2026-128122

MEDIUM 5.9

SvelteKit: Prerendered redirect paths can inject arbitrary rules into the `_redirects` file generated by `@sveltejs/adapter-cloudflare`

CVSS Score

5.9

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-79 CWE-93 CWE-116
Vendor	sveltejs
Product	kit
Published	Nov 13, 2026

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CVSS v3 Breakdown

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

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Affected Versions

sveltejs / kit

>= 4.7.0, < 7.2.10 >= 8.0.0-next.0, < 8.0.2

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/sveltejs/kit/security/advisories/GHSA-5wg4-q3ww-283h github.com: https://github.com/sveltejs/kit/pull/17620 github.com: https://github.com/sveltejs/kit/commit/0a2e58cbccdd46cac20aa5af4e2edf17e0da11dd github.com: https://github.com/sveltejs/kit/commit/679e0d84ea9951bb4f1e458a599066b5a451b08a github.com: https://github.com/sveltejs/kit/releases/tag/@sveltejs/[email protected] github.com: https://github.com/sveltejs/kit/releases/tag/@sveltejs/[email protected]