Plack::Middleware::XSendfile versions through 1.0053 for Perl can allow client-controlled path rewriting. Plack::Middleware::XSendfile allows the variation setting (sendfile type) to be set by the client via the X-Sendfile-Type header, if it is not considered in the middleware constructor or the Plack environment. A malicious client can set the X-Sendfile-Type header to "X-Accel-Redirect" to services running behind nginx reverse proxies, and then set the X-Accel-Mapping to map the path to an arbitrary file on the server. Since 1.0053, Plack::Middleware::XSendfile is deprecated and will be removed from future releases of Plack. This is similar to CVE-2025-61780 for Rack::Sendfile, although Plack::Middleware::XSendfile has some mitigations that disallow regular expressions to be used in the mapping, and only apply the mapping for the "X-Accel-Redirect" type.

• https://metacpan.org/release/MIYAGAWA/Plack-1.0053/changes
• https://metacpan.org/release/MIYAGAWA/Plack-1.0053/view/lib/Plack/Middleware/XSendfile.pm#DEPRECATION-NOTICE
• https://nvd.nist.gov/vuln/detail/CVE-2025-61780

Fixed a possible directory traversal with Plack::App::File on Win32.

Plack::App::File would previously strip trailing slashes off provided paths. This in combination with the common pattern of serving files with Plack::Middleware::Static could allow an attacker to bypass a whitelist of generated files

• https://github.com/plack/Plack/pull/446

Fixed directory traversal bug in Plack::App::File on win32 environments