Vulnerabilities > CVE-2022-31109 - HTTP Request Smuggling vulnerability in Getlaminas Laminas-Diactoros
Summary
laminas-diactoros is a PHP package containing implementations of the PSR-7 HTTP message interfaces and PSR-17 HTTP message factory interfaces. Applications that use Diactoros, and are either not behind a proxy, or can be accessed via untrusted proxies, can potentially have the host, protocol, and/or port of a `Laminas\Diactoros\Uri` instance associated with the incoming server request modified to reflect values from `X-Forwarded-*` headers. Such changes can potentially lead to XSS attacks (if a fully-qualified URL is used in links) and/or URL poisoning. Since the `X-Forwarded-*` headers do have valid use cases, particularly in clustered environments using a load balancer, the library offers mitigation measures only in the v2 releases, as doing otherwise would break these use cases immediately. Users of v2 releases from 2.11.1 can provide an additional argument to `Laminas\Diactoros\ServerRequestFactory::fromGlobals()` in the form of a `Laminas\Diactoros\RequestFilter\RequestFilterInterface` instance, including the shipped `Laminas\Diactoros\RequestFilter\NoOpRequestFilter` implementation which ignores the `X-Forwarded-*` headers. Starting in version 3.0, the library will reverse behavior to use the `NoOpRequestFilter` by default, and require users to opt-in to `X-Forwarded-*` header usage via a configured `Laminas\Diactoros\RequestFilter\LegacyXForwardedHeaderFilter` instance. Users are advised to upgrade to version 2.11.1 or later to resolve this issue. Users unable to upgrade may configure web servers to reject `X-Forwarded-*` headers at the web server level.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- HTTP Request Splitting HTTP Request Splitting (also known as HTTP Request Smuggling) is an attack pattern where an attacker attempts to insert additional HTTP requests in the body of the original (enveloping) HTTP request in such a way that the browser interprets it as one request but the web server interprets it as two. There are several ways to perform HTTP request splitting attacks. One way is to include double Content-Length headers in the request to exploit the fact that the devices parsing the request may each use a different header. Another way is to submit an HTTP request with a "Transfer Encoding: chunked" in the request header set with setRequestHeader to allow a payload in the HTTP Request that can be considered as another HTTP Request by a subsequent parsing entity. A third way is to use the "Double CR in an HTTP header" technique. There are also a few less general techniques targeting specific parsing vulnerabilities in certain web servers.
- HTTP Request Smuggling HTTP Request Smuggling results from the discrepancies in parsing HTTP requests between HTTP entities such as web caching proxies or application firewalls. Entities such as web servers, web caching proxies, application firewalls or simple proxies often parse HTTP requests in slightly different ways. Under specific situations where there are two or more such entities in the path of the HTTP request, a specially crafted request is seen by two attacked entities as two different sets of requests. This allows certain requests to be smuggled through to a second entity without the first one realizing it.