CVE-2026-114062
Description
A flaw was found in SvelteKit. This Server-Side Request Forgery (SSRF) vulnerability allows a remote attacker to access internal network services that should not be publicly accessible. By manipulating the HTTP Host or forwarded headers, an attacker can direct internal self-fetch fallback requests to a malicious server, which then redirects the application into querying internal systems.
Statement
This flaw is evaluated as Moderate severity because, although remotely triggerable without authentication, the impact is confined to unauthorized reads of internal network resources rather than arbitrary code execution or state alteration. The issue relies on servers processing untrusted reverse-proxy headers during self-fetch fallback operations, limiting exposure to applications designed to query their own endpoints in specific routing configurations. SvelteKit is not packaged or distributed in supported Red Hat Enterprise Linux products, significantly limiting the exposure for enterprise customer environments.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Application Data
Integrity
Technical Impact: Execute Unauthorized Code or Commands
Access Control
Technical Impact: Bypass Protection Mechanism
By providing URLs to unexpected hosts or ports, attackers can make it appear that the server is sending the request, possibly bypassing access controls such as firewalls that prevent the attackers from accessing the URLs directly. The server can be used as a proxy to conduct port scanning of hosts in internal networks, use other URLs such as that can access documents on the system (using file://), or use other protocols such as gopher:// or tftp://, which may provide greater control over the contents of requests.
Frequently Asked Questions
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