CVE-2013-4135 in OpenAFS
Summary
by MITRE
The vos command in OpenAFS 1.6.x before 1.6.5, when using the -encrypt option, only enables integrity protection and sends data in cleartext, which allows remote attackers to obtain sensitive information by sniffing the network.
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Analysis
by VulDB Data Team • 01/10/2022
The vulnerability identified as CVE-2013-4135 affects OpenAFS versions 1.6.x prior to 1.6.5, specifically within the vos command functionality when utilizing the -encrypt option. This flaw represents a critical security oversight in the authentication and data protection mechanisms of the OpenAFS distributed file system. The vulnerability stems from improper implementation of encryption protocols where the system fails to provide comprehensive security measures for data transmission. When administrators or users execute the vos command with the -encrypt flag, the system erroneously enables only integrity protection while leaving the actual data payload in cleartext format during network transmission. This design flaw creates a significant attack surface that exposes sensitive information to unauthorized parties who can intercept network traffic through passive sniffing techniques.
The technical nature of this vulnerability aligns with CWE-310, which addresses cryptographic issues related to improper implementation of cryptographic protocols. The flaw specifically manifests as a failure to implement proper encryption for data in transit, creating a scenario where network traffic analysis can reveal sensitive information without requiring active exploitation or advanced attack vectors. The vos command in OpenAFS serves as a critical administrative tool for managing volume servers, and when used with the -encrypt option, it should provide end-to-end encryption for all transmitted data. However, the implementation defect means that while the system may indicate encryption is active, the actual data transmission remains vulnerable to eavesdropping attacks. This misconfiguration essentially creates a false sense of security where administrators believe their data is protected while it remains accessible to network sniffers.
From an operational perspective, this vulnerability poses severe risks to organizations relying on OpenAFS for distributed file services. Remote attackers with network access can easily capture and analyze traffic to extract sensitive information including authentication credentials, file contents, and administrative commands. The impact extends beyond simple data leakage to potentially enable further attacks including privilege escalation, lateral movement within the network, and unauthorized access to critical system resources. The vulnerability affects the confidentiality aspect of the CIA triad by failing to protect data in transit, which represents a fundamental security requirement for any distributed system handling sensitive information. Organizations using OpenAFS versions prior to 1.6.5 face significant exposure to man-in-the-middle attacks and passive reconnaissance activities that could compromise entire network infrastructures.
The remediation approach for CVE-2013-4135 requires immediate patching of OpenAFS installations to version 1.6.5 or later, which contains the necessary fixes to properly implement encryption for all data transmitted through the vos command. System administrators should conduct comprehensive audits of their OpenAFS deployments to identify all instances running vulnerable versions and ensure proper patch management protocols are in place. Additionally, organizations should implement network segmentation and monitoring solutions to detect and prevent unauthorized network sniffing activities. The ATT&CK framework categorizes this vulnerability under T1041, which deals with Exfiltration Over C2 Channel, as attackers can leverage this weakness to extract sensitive data from the network. Security teams should also consider implementing additional layers of protection such as encrypted network tunnels and enhanced monitoring of administrative commands to prevent exploitation of this vulnerability. Proper configuration management and regular security assessments are essential to prevent similar issues in other network services and protocols.