CVE-2017-16816 in HTCondor
Summary
by MITRE
The condor_schedd component in HTCondor before 8.6.8 and 8.7.x before 8.7.5 allows remote authenticated users to cause a denial of service (daemon crash) by leveraging use of GSI and VOMS extensions.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 02/25/2020
The vulnerability identified as CVE-2017-16816 affects the condor_schedd component within HTCondor, a distributed computing system designed for high throughput computing environments. This flaw exists in versions prior to 8.6.8 and 8.7.x before 8.7.5, representing a significant security concern for organizations relying on HTCondor for job scheduling and resource management. The vulnerability specifically targets the authentication and authorization mechanisms that utilize Grid Security Infrastructure (GSI) and Virtual Organization Membership Service (VOMS) extensions, which are commonly employed in high energy physics and other scientific computing environments where trust relationships between distributed systems must be established.
The technical implementation of this vulnerability stems from improper handling of GSI and VOMS authentication tokens within the condor_schedd daemon process. When remote authenticated users leverage these extensions, the system fails to properly validate or sanitize the authentication data structures, leading to memory corruption or invalid state conditions that ultimately result in daemon crashes. This represents a classic denial of service scenario where legitimate users can disrupt system operations through crafted authentication requests. The vulnerability manifests during the processing of authentication credentials that include VOMS attributes, which are used to establish user privileges and access controls within the distributed computing environment.
From an operational impact perspective, this vulnerability creates substantial risk for organizations using HTCondor in production environments, particularly those in scientific computing domains where job scheduling is critical for research operations. The denial of service condition can result in complete disruption of job submission and execution capabilities, forcing administrators to restart daemons manually and potentially causing loss of computational work. The remote authenticated nature of the attack means that adversaries with valid credentials can exploit this vulnerability, making it particularly dangerous in environments where credential management is complex. Organizations may experience cascading failures in their distributed computing infrastructure as the schedd daemon becomes unavailable, affecting multiple dependent services and user workflows.
Mitigation strategies for CVE-2017-16816 primarily involve upgrading to patched versions of HTCondor, specifically versions 8.6.8 and 8.7.5 or later, which contain the necessary code modifications to properly handle GSI and VOMS authentication data. System administrators should also implement monitoring solutions to detect unusual daemon crash patterns and establish automated alerting for service availability. The vulnerability aligns with CWE-121, which addresses stack-based buffer overflow conditions, and relates to ATT&CK technique T1499.004 for network denial of service attacks. Additional defensive measures include implementing network segmentation to limit access to the schedd component, enforcing strict access controls for authentication tokens, and regularly auditing authentication processes to identify potential exploitation attempts. Organizations should also consider implementing intrusion detection systems specifically configured to monitor for patterns associated with this vulnerability.