CVE-2014-5352 in Kerberos
Summary
by MITRE
The krb5_gss_process_context_token function in lib/gssapi/krb5/process_context_token.c in the libgssapi_krb5 library in MIT Kerberos 5 (aka krb5) through 1.11.5, 1.12.x through 1.12.2, and 1.13.x before 1.13.1 does not properly maintain security-context handles, which allows remote authenticated users to cause a denial of service (use-after-free and double free, and daemon crash) or possibly execute arbitrary code via crafted GSSAPI traffic, as demonstrated by traffic to kadmind.
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Analysis
by VulDB Data Team • 03/08/2022
The vulnerability identified as CVE-2014-5352 represents a critical security flaw within the MIT Kerberos 5 implementation that affects multiple versions of the libgssapi_krb5 library. This issue stems from improper handling of security context handles during the krb5_gss_process_context_token function execution, creating a scenario where authenticated remote attackers can manipulate GSSAPI traffic to trigger system instability. The vulnerability specifically impacts the kerberos authentication infrastructure that is widely deployed across enterprise environments and network services relying on secure authentication protocols. The flaw manifests when the library fails to properly manage memory references associated with security contexts, leading to dangerous memory corruption states that can be exploited by malicious actors.
The technical nature of this vulnerability involves a use-after-free condition and potential double free errors that occur when processing crafted GSSAPI tokens through the kadmind service. When an authenticated user sends specially crafted tokens to the kadmind daemon, the function processes these tokens without adequate validation of context handle states, causing the system to attempt to access freed memory locations or perform duplicate memory deallocations. This improper memory management creates opportunities for attackers to either crash the kerberos daemon through controlled crashes or potentially execute arbitrary code by manipulating the memory layout. The vulnerability is particularly concerning because it requires only authenticated access to exploit, meaning that any user with valid credentials within the kerberos realm can potentially trigger the malicious behavior. The flaw demonstrates poor adherence to secure coding practices and represents a classic example of memory safety issues that can lead to privilege escalation or system compromise.
The operational impact of CVE-2014-5352 extends beyond simple denial of service scenarios to potentially enable remote code execution within the targeted kerberos infrastructure. When exploited, this vulnerability can cause critical kerberos services to crash, disrupting authentication services for entire domains and potentially affecting downstream applications that depend on kerberos for secure authentication. The vulnerability affects the core authentication infrastructure that underpins many enterprise security systems, including Active Directory integration, network authentication services, and various enterprise applications that rely on kerberos for secure communications. Organizations using affected versions of MIT Kerberos 5 face significant risk of service disruption and potential compromise of their authentication infrastructure. The impact is particularly severe in environments where kadmind is exposed to untrusted networks or where multiple authentication services depend on the stability of the kerberos daemon. The vulnerability also impacts compliance with security standards such as those outlined in the NIST Cybersecurity Framework and ISO 27001 requirements for secure authentication systems.
Mitigation strategies for CVE-2014-5352 primarily involve immediate patching of affected systems to the latest stable versions of MIT Kerberos 5 that contain the necessary memory management fixes. Organizations should prioritize updating all kerberos daemon components including kadmind, kdc, and related services to versions that have addressed the security context handle management issues. Additionally, network segmentation and access controls should be implemented to limit exposure of kerberos services to untrusted networks, reducing the attack surface for potential exploitation. Security monitoring should be enhanced to detect unusual GSSAPI traffic patterns that might indicate exploitation attempts, particularly around kadmind service communications. The vulnerability aligns with CWE-415 and CWE-416 categories related to double free and use-after-free errors, and represents a technique that could be mapped to ATT&CK tactics such as privilege escalation and denial of service. Organizations should also consider implementing intrusion detection systems that can identify and alert on malformed GSSAPI traffic patterns that could indicate exploitation attempts. Regular security assessments and vulnerability scanning should be conducted to ensure complete remediation across all kerberos-dependent systems within the organization's infrastructure.