CVE-2026-17552 Server-side request forgery in Plack::App::Prerender
Attackers can force the application to proxy requests to arbitrary internal hosts, bypassing network restrictions and accessing sensitive data.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-17552?
CVE-2026-17552 is a critical server-side request forgery vulnerability in RRWO Plack::App::Prerender, published on 27 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-918
Which versions are affected by CVE-2026-17552?
How do I fix CVE-2026-17552?
No fix has been published for CVE-2026-17552 yet. Limit exposure of the affected software until one is available.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-17552 being exploited?
There is no known exploitation of CVE-2026-17552 in the wild and no public exploit code.
Sources
Also known as GHSA-6x4w-x68j-ppqq.