CVE-2001-0388 in FreeBSD
Summary
by MITRE
time server daemon timed allows remote attackers to cause a denial of service via malformed packets.
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Analysis
by VulDB Data Team • 06/25/2021
The vulnerability identified as CVE-2001-0388 affects the time server daemon timed, which is part of the internet time protocol implementation commonly found in unix-like operating systems. This flaw resides in the daemon's handling of network packets, specifically when processing time synchronization requests from remote clients. The issue manifests when the timed daemon receives malformed or improperly formatted packets that it cannot properly parse or validate, leading to unexpected behavior in the service operation.
The technical nature of this vulnerability stems from inadequate input validation within the timed daemon's packet processing routines. When remote attackers send specially crafted malformed packets to the time server, the daemon fails to properly handle these inputs and subsequently crashes or becomes unresponsive. This occurs because the daemon lacks proper error handling mechanisms to deal with unexpected packet structures or data formats that fall outside the expected protocol specifications. The vulnerability operates at the network protocol level, targeting the time synchronization service that many systems rely upon for accurate timekeeping and logging purposes.
From an operational perspective, this vulnerability presents a significant denial of service risk to affected systems. When exploited successfully, attackers can render time synchronization services unavailable, which impacts not only the timekeeping capabilities of individual systems but also affects various security and administrative functions that depend on synchronized time stamps. The timed daemon's role in maintaining system time accuracy makes this vulnerability particularly dangerous as it can compromise audit trails, authentication mechanisms, and other time-sensitive security operations. The attack requires minimal resources from the attacker while potentially causing widespread service disruption across networks that rely on time synchronization protocols.
Mitigation strategies for this vulnerability should focus on implementing proper input validation and error handling within the timed daemon's codebase. System administrators should ensure that all network services properly validate incoming packets before processing them, implementing robust parsing routines that can gracefully handle malformed data. The vulnerability aligns with CWE-129, which addresses improper validation of input buffers, and represents a classic example of how insufficient input sanitization can lead to service disruption. Organizations should also consider implementing network segmentation and access controls to limit exposure of time servers to untrusted networks, while regularly updating system software to include security patches. The ATT&CK framework categorizes this as a denial of service attack vector through protocol manipulation, highlighting the importance of network protocol resilience and proper service hardening practices.