جزئیات آسیب‌پذیری

Dancer2 versions from 2.1.0 before 2.2.0 for Perl serve files from outside public_dir via relative path segments in the File route handler. The handler joins the request path onto public_dir without collapsing relative segments, and checks only that the result is a readable regular file. A request for `/../outside.txt` escapes public_dir, and percent-encoding the dots reaches the same file. The handler is off by default. An application is affected once it names File in route_handlers and sets static_handler to 0, which otherwise refuses a dot segment before the route runs. Any file the worker process can read is served to an unauthenticated request, including the application's config.yml above public_dir.

• https://github.com/PerlDancer/Dancer2/security/advisories/GHSA-6xw8-v24c-m783 vendor-advisory
• https://github.com/PerlDancer/Dancer2/commit/2446a09ffb83fef71cc75c327bd6e4b1f007b885.patch patch
• https://metacpan.org/release/CROMEDOME/Dancer2-2.2.0/changes release-notes
• http://www.openwall.com/lists/oss-security/2026/09/22/4