Review reviewCritical

CVE-2026-17552

RRWO Plack::App::Prerender

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...

CVSS: 9.1
EPSS: 0.35%
CISA KEV: Not listed
Published: 2026.07.28

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.35%

Technical severityCVSS 9.1

Vulnerability overview

Affected product and versions

Product: RRWO Plack::App::Prerender
Affected versions: < 0.3.0
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that RRWO Plack::App::Prerender and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CWE: CWE-918