CVE-2016-1384 in IOS
Summary
by MITRE
The NTP implementation in Cisco IOS 15.1 and 15.5 and IOS XE 3.2 through 3.17 allows remote attackers to modify the system time via crafted packets, aka Bug ID CSCux46898.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 10/14/2024
The vulnerability identified as CVE-2016-1384 represents a critical security flaw in the Network Time Protocol implementation within Cisco IOS and IOS XE operating systems. This issue affects versions 15.1 and 15.5 of IOS along with IOS XE versions 3.2 through 3.17, creating a significant attack surface for malicious actors seeking to manipulate system time synchronization mechanisms. The vulnerability specifically resides in how the NTP daemon processes incoming time synchronization packets, allowing unauthorized modification of system time through carefully crafted malicious packets.
The technical exploitation of this vulnerability stems from insufficient input validation within the NTP implementation, which fails to properly verify the authenticity and integrity of time synchronization packets received from remote sources. Attackers can construct specially formatted NTP packets that, when processed by the vulnerable Cisco devices, cause the system to accept and apply incorrect time values. This flaw operates at the network protocol level and leverages the trust relationship inherent in time synchronization protocols, where legitimate time servers are expected to provide accurate time information without additional authentication verification.
From an operational impact perspective, this vulnerability poses severe risks to network infrastructure security and system integrity. When an attacker successfully modifies the system time, it can disrupt time-sensitive operations, compromise security logging mechanisms, and potentially enable further attacks that rely on time-based validation checks. The modification of system time can invalidate security certificates, disrupt authentication processes, and affect the proper functioning of network services that depend on accurate time synchronization. This vulnerability directly impacts the confidentiality, integrity, and availability of network services by allowing unauthorized modification of critical system parameters.
The exploitation of CVE-2016-1384 aligns with several attack patterns documented in the MITRE ATT&CK framework, particularly those related to system time manipulation and privilege escalation techniques. This vulnerability can be classified under CWE-20 as "Improper Input Validation" and represents a specific instance of how inadequate validation of network protocol inputs can lead to system compromise. The attack vector typically involves network-based reconnaissance followed by packet crafting and delivery to vulnerable systems, making it particularly dangerous in environments where network access is not properly restricted.
Organizations should implement immediate mitigations including applying the latest Cisco security patches and updates that address this specific vulnerability, configuring NTP access controls to restrict time synchronization sources to trusted entities, and implementing network segmentation to limit exposure of vulnerable devices. Additional protective measures include monitoring NTP traffic for anomalous packet patterns, implementing network access control lists to restrict NTP traffic, and establishing robust time synchronization monitoring procedures. The vulnerability demonstrates the critical importance of validating all network inputs and maintaining up-to-date security configurations to prevent unauthorized modification of system time parameters that are fundamental to network security operations.