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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.35%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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://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.
- CVSS 3.1
- 9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- EPSS
- 0.35% probability · 28th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-918
- Source
- 9b29abf9-4ab0-4765-b253-1875cd9b441e
References
- https://github.com/robrwo/perl-Plack-App-Prerender/commit/2d793dd69e2b6f4e469618ee742bd8402677202d.patch
- 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
- http://www.openwall.com/lists/oss-security/2026/07/28/3
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.