Synopse

A variety of programming languages suffer from a denial-of-service (DoS) condition against storage functions of key/value pairs in hash data structures, the condition can be leveraged by exploiting predictable collisions in the underlying hashing algorithms.

The issue finds particular exposure in web server applications and/or frameworks. In particular, the lack of sufficient limits for the number of parameters in POST requests in conjunction with the predictable collision properties in the hashing functions of the underlying languages can render web applications vulnerable to the DoS condition. The attacker, using specially crafted HTTP requests, can lead to a 100% of CPU usage which can last up to several hours depending on the targeted application and server performance, the amplification effect is considerable and requires little bandwidth and time on the attacker side.

Source: #2011-003 multiple implementations denial-of-service via hash algorithm collision

Commonly, it can be achieved, in the SOA over HTTP world via:
- HTTP basic auth over HTTPS;
- Cookies and session management;
- Query Authentication with additional signature parameters.

We'll have to adapt, or even better mix those techniques, to match our framework architecture at best.

Each authentication scheme has its own PROs and CONs, depending on the purpose of your security policy and software architecture.