CVE-2026-17552
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://example.com@192.168.1.2/", 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.
Package Versions Affected
Automatically patch vulnerabilities without upgrading
CVSS Version
Related Resources
References
http://www.openwall.com/lists/oss-security/2026/07/28/3, https://cpan.org/modules, https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/17xxx/CVE-2026-17552.json, https://github.com/robrwo/perl-Plack-App-Prerender/security/advisories/GHSA-6x4w-x68j-ppqq, https://metacpan.org/release/RRWO/Plack-App-Prerender-v0.3.0/changes, https://nvd.nist.gov/vuln/detail/CVE-2026-17552, https://github.com/robrwo/perl-Plack-App-Prerender/commit/2d793dd69e2b6f4e469618ee742bd8402677202d.patch, https://github.com/robrwo/perl-Plack-App-Prerender