/ 
Plack-1.0055
⭐ Starred 488 / Plack::Middleware::SimpleContentFilter
Security Advisories (1)
CVE-2026-115825 (2026-10-25)

HTTP::Server::PSGI versions before 1.0056 for Perl allow a single request to crash the server by declaring a large Content-Length. The request body is read with sysread() calls sized by the remaining Content-Length. Perl grows the read buffer to the requested length before any data arrives, so the server tries to allocate as much memory as the client declares. A remote attacker can send one request with a large Content-Length and a few body bytes, and perl exits with an out-of-memory error before the application is called. HTTP::Server::PSGI runs as a single process, so the server stays down until restarted.

NAME

Plack::Middleware::SimpleContentFilter - Filters response content

SYNOPSIS

use Plack::Builder;

my $app = sub {
    return [ 200, [ 'Content-Type' => 'text/plain' ], [ 'Hello Foo' ] ];
};

builder {
    enable "Plack::Middleware::SimpleContentFilter",
        filter => sub { s/Foo/Bar/g; };
    $app;
};

DESCRIPTION

This middleware should be considered as a demo. Running this against your application might break your HTML unless you code the filter callback carefully.

Plack::Middleware::SimpleContentFilter is a simple content text filter to run against response body. This middleware is only enabled against responses with text/* Content-Type.

AUTHOR

Tatsuhiko Miyagawa