CWE-836

Base Abstraction Level
Pillar — Highest-level weakness category
Class — Abstract, language-independent
Base — Specific enough to detect
Variant — Tied to specific technology
Compound — Requires multiple weaknesses Incomplete MITRE CWE Status
Stable — Fully reviewed and complete
Draft — Under development, may change
Incomplete — Partially defined by MITRE
Deprecated — No longer recommended
Obsolete — Replaced by another CWE
Use of Password Hash Instead of Password for Authentication

Description

The product records password hashes in a data store, receives a hash of a password from a client, and compares the supplied hash to the hash obtained from the data store.

Some authentication mechanisms rely on the client to generate the hash for a password, possibly to reduce load on the server or avoid sending the password across the network. However, when the client is used to generate the hash, an attacker can bypass the authentication by obtaining a copy of the hash, e.g. by using SQL injection to compromise a database of authentication credentials, or by exploiting an information exposure. The attacker could then use a modified client to replay the stolen hash without having knowledge of the original password. As a result, the server-side comparison against a client-side hash does not provide any more security than the use of passwords without hashing.

Consequences

Access Control — Bypass Protection Mechanism, Gain Privileges or Assume Identity

An attacker could bypass the authentication routine without knowing the original password.