CVE-2026-17552
CriticalCVSS 9.1Exploitation Probability (EPSS)
Low risk9th percentile - higher than 9% of all known CVEs
Summary
A vulnerability in Plack::App::Prerender before version 0.3.0 for Perl allows proxying to an arbitrary host via unvalidated REQUEST_URI concatenation. When the rewrite base is a plain string, the REQUEST_URI is appended without checking if the path starts with a forward slash. An attacker can change the host by sending a request starting with '@', enabling access to internal or restricted hosts.
Risk Assessment
An attacker can access internal or restricted network resources that the web server has access to, potentially leading to data leakage or further attacks on internal infrastructure.
Recommendation
Upgrade Plack::App::Prerender to version 0.3.0 or later, which includes proper path validation.
Original NVD description (English source)
Plack::App::Prerender versions before 0.3.0 for Perl can proxy to an arbitrary host via unvalidated REQUEST_URI concatenation in call. When the rewrite base is a plain string, the REQUEST_URI is appended to it, with no check that the path starts with a forward slash ('/'). When the rewrite base does not contain a path (which is the standard given in the SYNOPSIS), an attacker can create a request that changes the hostname. A request target starting with an at-sign ('@') changes the base to a RFC 3986 userinfo component. For example, a rewrite base of "https://example.com" with the submitted request "GET @192.168.1.2/" will send a request to "https://[email protected]/", with the rendered content returned to the attacker. This allows an attacker to access internal or restricted hosts that only the webserver has access to.