CVE-2008-1677 in Directory Server
Summary
by MITRE
Buffer overflow in the regular expression handler in Red Hat Directory Server 8.0 and 7.1 before SP6 allows remote attackers to cause a denial of service (slapd crash) and possibly execute arbitrary code via a crafted LDAP query that triggers the overflow during translation to a regular expression.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 08/10/2019
The vulnerability identified as CVE-2008-1677 represents a critical buffer overflow flaw within the regular expression processing component of Red Hat Directory Server versions 7.1 through 8.0, specifically before service pack 6. This security weakness resides in the slapd daemon responsible for handling Lightweight Directory Access Protocol queries and demonstrates the dangerous intersection of string manipulation and memory corruption in directory services. The flaw occurs during the translation process of LDAP queries into regular expression patterns, creating a scenario where malformed input can trigger unintended memory behavior.
The technical implementation of this vulnerability stems from inadequate bounds checking within the regular expression handler module. When processing LDAP queries that contain specially crafted regular expressions, the system fails to properly validate input lengths against allocated buffer boundaries. This condition creates a classic buffer overflow scenario where attacker-controlled data can overwrite adjacent memory locations, potentially corrupting critical program state or execution flow. The vulnerability operates at the level of the slapd service, making it accessible to remote attackers who can submit malicious LDAP queries without requiring authentication, thereby presenting a significant threat to directory service availability and integrity.
The operational impact of this vulnerability extends beyond simple denial of service to potentially enabling remote code execution, making it particularly dangerous for enterprise environments relying on directory services for authentication and authorization. A successful exploitation could result in complete system compromise, allowing attackers to execute arbitrary code with the privileges of the slapd process, which typically runs with elevated system permissions. The denial of service aspect alone can severely disrupt enterprise operations, as directory servers serve as foundational components for authentication, single sign-on, and access control across numerous applications and services within an organization's infrastructure.
This vulnerability maps directly to CWE-121, which describes heap-based buffer overflow conditions, and aligns with ATT&CK technique T1190 for exploitation of remote services through buffer overflow mechanisms. Organizations affected by this vulnerability should immediately implement mitigation strategies including applying the vendor-provided patches for Red Hat Directory Server versions 7.1 through 8.0, implementing network segmentation to limit access to directory services, and deploying intrusion detection systems to monitor for suspicious LDAP query patterns. Additionally, administrators should consider disabling unnecessary regular expression processing features and implementing input validation controls at the network perimeter to reduce the attack surface. The remediation process should include comprehensive testing of patched systems to ensure that the vulnerability has been properly addressed without introducing regressions in directory service functionality.