Server-Side Route Resolution Vulnerability in SvelteKit Framework
CVE-2026-128116

5.3MEDIUM

Key Information:

Vendor

Sveltejs

Status
Kit
Vendor
CVE Published:
13 November 2026

What is CVE-2026-128116?

A vulnerability exists in SvelteKit that allows applications configured with router.resolution set to 'server' to misinterpret pathnames starting with '//' as protocol-relative module specifiers during client-side navigation. This could enable a socially engineered link to load and execute JavaScript from an unauthorized origin in the user's browser. The issue has been addressed in versions 2.70.4 and 3.1.1, underscoring the importance of updating to these versions to safeguard against such exploitation.

Affected Version(s)

kit < 2.70.4 < 2.70.4

kit >= 3.0.0, < 3.1.1 < 3.0.0, 3.1.1

References

https://github.com/sveltejs/kit/security/advisories/GHSA-...
x_refsource_CONFIRM
https://github.com/sveltejs/kit/pull/17620
x_refsource_MISC
https://github.com/sveltejs/kit/commit/0a2e58cbccdd46cac2...
x_refsource_MISC

CVSS V3.1

Score:
5.3
Severity:
MEDIUM
Confidentiality:
High
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.