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.
Potential Impact
Access Control
Bypass Protection Mechanism, Gain Privileges or Assume Identity
Real-World CVE Examples
| CVE ID | Description |
|---|---|
| CVE-2009-1283 | Product performs authentication with user-supplied password hashes that can be obtained from a separate SQL injection vulnerability (CVE-2009-1282). |
| CVE-2005-3435 | Product allows attackers to bypass authentication by obtaining the password hash for another user and specifying the hash in the pwd argument. |
Related Weaknesses
Frequently Asked Questions
What is CWE-836?
CWE-836 (Use of Password Hash Instead of Password for Authentication) is a software weakness identified by MITRE's Common Weakness Enumeration. It is classified as a Base-level weakness. 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.
How can CWE-836 be exploited?
Attackers can exploit CWE-836 (Use of Password Hash Instead of Password for Authentication) to bypass protection mechanism, gain privileges or assume identity. This weakness is typically introduced during the Implementation phase of software development.
How do I prevent CWE-836?
Follow secure coding practices, conduct code reviews, and use automated security testing tools (SAST/DAST) to detect this weakness early in the development lifecycle.
What is the severity of CWE-836?
CWE-836 is classified as a Base-level weakness (Medium abstraction). It has been observed in 2 real-world CVEs.