CWE-759: Use of a One-Way Hash without a Salt

Description:
The product uses a one-way cryptographic hash against an input that should not be reversible, such as a password, but the product does not also use a salt as part of the input.

Extended Description:
This makes it easier for attackers to pre-compute the hash value using dictionary attack techniques such as rainbow tables. 
             It should be noted that, despite common perceptions, the use of a good salt with a hash does not sufficiently increase the effort for an attacker who is targeting an individual password, or who has a large amount of computing resources available, such as with cloud-based services or specialized, inexpensive hardware. Offline password cracking can still be effective if the hash function is not expensive to compute; many cryptographic functions are designed to be efficient and can be vulnerable to attacks using massive computing resources, even if the hash is cryptographically strong. The use of a salt only slightly increases the computing requirements for an attacker compared to other strategies such as adaptive hash functions. See CWE-916 for more details.

Affected languages: Not Language-Specific
Parent weaknesses: CWE-916

Consequences:
  - Access Control: Bypass Protection Mechanism

Detection methods:
  - Automated Static Analysis - Binary or Bytecode: According to SOAR [REF-1479], the following detection techniques may be useful: 
                   
                      Cost effective for partial coverage: 
                         
             
  - Manual Static Analysis - Binary or Bytecode: According to SOAR [REF-1479], the following detection techniques may be useful: 
                   
                      Cost effective for partial coverage: 
                         
             
  - Manual Static Analysis - Source Code: According to SOAR [REF-1479], the following detection techniques may be useful: 
                   
                      Highly cost effective: 
                         
                           
  - Automated Static Analysis - Source Code: According to SOAR [REF-1479], the following detection techniques may be useful: 
                   
                      Highly cost effective: 
                         
                           

Mitigations:
  - [Architecture and Design] Use an adaptive hash function that can be configured to change the amount of computational effort needed to compute the hash, such as the number of iterations ("stretching") or the amount of memory required. Some hash functions perform salting automatically. These functions can significantly increas
  - [Architecture and Design] If a technique that requires extra computational effort can not be implemented, then for each password that is processed, generate a new random salt using a strong random number generator with unpredictable seeds. Add the salt to the plaintext password before hashing it. When storing the hash, also 
  - [Implementation] When using industry-approved techniques, use them correctly. Don't cut corners by skipping resource-intensive steps (CWE-325). These steps are often essential for preventing common attacks.

Demonstrative examples:
In both of these examples, a user is logged in if their given password matches a stored password:
This code relies exclusively on a password mechanism (CWE-309) using only one factor of authentication (CWE-308). If an attacker can steal or guess a user's password, they are given full access to their account. Note this code also uses SHA-1, which is a weak hash (CWE-328).  It also does not use a salt (CWE-759).
unsigned char *check_passwd(char *plaintext) { ctext = simple_digest("sha1",plaintext,strlen(plaintext), ... ); 
                         //Login if hash matches stored hash 
                         if (equal(ctext, secret_password())) { login_user(); } }
String plainText = new String(plainTextIn); MessageDigest encer = MessageDigest.getInstance("SHA"); encer.update(plainTextIn); by

In this example, a new user provides a new username and password to create an account. The program hashes the new user's password then stores it in a database.
While it is good to avoid storing a cleartext password, the program does not provide a salt to the hashing function, thus increasing the chances of an attacker being able to reverse the hash and discover the original password if the database is compromised.
def storePassword(userName,Password): hasher = hashlib.new('md5') hasher.update(Password) hashed[CREDENTIAL_REDACTED].digest() 
                         
                         # UpdateUserLogin returns True on success, False otherwise 
                         return updateUserLogin(userName,hashedPassword)
def storePassword(userName,Password): hasher = hashlib.new('md5',b'SaltGoe

Real-world examples:
  - CVE-2008-1526: Router does not use a salt with a hash, making it easier to crack passwords.
  - CVE-2006-1058: Router does not use a salt with a hash, making it easier to crack passwords.