CAPEC-136: LDAP Injection
Description
An attacker manipulates or crafts an LDAP query for the purpose of undermining the security of the target. Some applications use user input to create LDAP queries that are processed by an LDAP server. For example, a user might provide their username during authentication and the username might be inserted in an LDAP query during the authentication process. An attacker could use this input to inject additional commands into an LDAP query that could disclose sensitive information. For example, entering a * in the aforementioned query might return information about all users on the system. This attack is very similar to an SQL injection attack in that it manipulates a query to gather additional information or coerce a particular return value.
- Likelihood of attack
- High
- Typical severity
- High
- Abstraction
- StandardA specific methodology or technique used in an attack.
Mechanism of attack: Inject Unexpected Items
Prerequisites
- The target application must accept a string as user input, fail to sanitize characters that have a special meaning in LDAP queries in the user input, and insert the user-supplied string in an LDAP query which is then processed.
Skills required
- MediumThe attacker needs to have knowledge of LDAP, especially its query syntax.
Consequences
- Availability
Unreliable Execution
- Integrity
Modify Data
- Confidentiality
Read Data
- Authorization
Execute Unauthorized Commands
Run Arbitrary Code
- AccountabilityAuthenticationAuthorizationNon-Repudiation
Gain Privileges
- Access ControlAuthorization
Bypass Protection Mechanism
Mitigations
- Strong input validation - All user-controllable input must be validated and filtered for illegal characters as well as LDAP content.
- Use of custom error pages - Attackers can glean information about the nature of queries from descriptive error messages. Input validation must be coupled with customized error pages that inform about an error without disclosing information about the LDAP or application.