Traefik is an open source HTTP reverse proxy and load balancer. When a request is sent to Traefik with a URL fragment, Traefik automatically URL encodes and forwards the fragment to the backend server. This violates RFC 7230 because in the origin-form the URL should only contain the absolute path and the query. When this is combined with another frontend proxy like Nginx, it can be used to bypass frontend proxy URI-based access control restrictions. This vulnerability has been addressed in versions 2.10.6 and 3.0.0-beta5. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Fiber is a web framework for Go. In github.com/gofiber/fiber/v3 versions through 3.1.0, the default key generator in the cache middleware uses only the request path and does not include the query string. As a result, requests for the same path with different query parameters can share a cache key and receive the wrong cached response. This can cause response mix-up for query-dependent endpoints and may expose data intended for a different request. This issue is fixed after version 3.1.0.

Rack is a modular Ruby web server interface. From versions 3.0.0.beta1 to before 3.1.21 and 3.2.0 to before 3.2.6, Rack::Utils.forwarded_values parses the RFC 7239 Forwarded header by splitting on semicolons before handling quoted-string values. Because quoted values may legally contain semicolons, a header can be interpreted by Rack as multiple Forwarded directives rather than as a single quoted for value. In deployments where an upstream proxy, WAF, or intermediary validates or preserves quoted Forwarded values differently, this discrepancy can allow an attacker to smuggle host, proto, for, or by parameters through a single header value. This issue has been patched in versions 3.1.21 and 3.2.6.

Bref enable serverless PHP on AWS Lambda. When Bref is used in combination with an API Gateway with the v2 format, it does not handle multiple values headers. If PHP generates a response with two headers having the same key but different values only the latest one is kept. If an application relies on multiple headers with the same key being set for security reasons, then Bref would lower the application security. For example, if an application sets multiple `Content-Security-Policy` headers, then Bref would just reflect the latest one. This vulnerability is patched in 2.1.13.

Netty project is an event-driven asynchronous network application framework. Starting in version 4.1.83.Final and prior to 4.1.86.Final, when calling `DefaultHttpHeadesr.set` with an _iterator_ of values, header value validation was not performed, allowing malicious header values in the iterator to perform HTTP Response Splitting. This issue has been patched in version 4.1.86.Final. Integrators can work around the issue by changing the `DefaultHttpHeaders.set(CharSequence, Iterator<?>)` call, into a `remove()` call, and call `add()` in a loop over the iterator of values.

silverstripe-omnipay is a SilverStripe integration with Omnipay PHP payments library. For a subset of Omnipay gateways (those that use intermediary states like `isNotification()` or `isRedirect()`), if the payment identifier or success URL is exposed it is possible for payments to be prematurely marked as completed without payment being taken. This is mitigated by the fact that most payment gateways hide this information from users, however some issuing banks offer flawed 3DSecure implementations that may inadvertently expose this data. The following versions have been patched to fix this issue: `2.5.2`, `3.0.2`, `3.1.4`, and `3.2.1`. There are no known workarounds for this vulnerability.