Vulnerabilities > CVE-2024-23644 - Interpretation Conflict vulnerability in Trillium and Trillium-Http
Summary
Trillium is a composable toolkit for building internet applications with async rust. In `trillium-http` prior to 0.3.12 and `trillium-client` prior to 0.5.4, insufficient validation of outbound header values may lead to request splitting or response splitting attacks in scenarios where attackers have sufficient control over headers. This only affects use cases where attackers have control of request headers, and can insert "\r\n" sequences. Specifically, if untrusted and unvalidated input is inserted into header names or values. Outbound `trillium_http::HeaderValue` and `trillium_http::HeaderName` can be constructed infallibly and were not checked for illegal bytes when sending requests from the client or responses from the server. Thus, if an attacker has sufficient control over header values (or names) in a request or response that they could inject `\r\n` sequences, they could get the client and server out of sync, and then pivot to gain control over other parts of requests or responses. (i.e. exfiltrating data from other requests, SSRF, etc.) In `trillium-http` versions 0.3.12 and later, if a header name is invalid in server response headers, the specific header and any associated values are omitted from network transmission. Additionally, if a header value is invalid in server response headers, the individual header value is omitted from network transmission. Other headers values with the same header name will still be sent. In `trillium-client` versions 0.5.4 and later, if any header name or header value is invalid in the client request headers, awaiting the client Conn returns an `Error::MalformedHeader` prior to any network access. As a workaround, Trillium services and client applications should sanitize or validate untrusted input that is included in header values and header names. Carriage return, newline, and null characters are not allowed.
Vulnerable Configurations
| Part | Description | Count |
|---|---|---|
| Application | 2 |
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 Response Smuggling An attacker injects content into a server response that is interpreted differently by intermediaries than it is by the target browser. To do this, it takes advantage of inconsistent or incorrect interpretations of the HTTP protocol by various applications. For example, it might use different block terminating characters (CR or LF alone), adding duplicate header fields that browsers interpret as belonging to separate responses, or other techniques. Consequences of this attack can include response-splitting, cross-site scripting, apparent defacement of targeted sites, cache poisoning, or similar actions.
- 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.