CVE-2026-26076 is a vulnerability classified under CWE-770 (Allocation of Resources Without Limits or Throttling) affecting the ntpd-rs implementation of the Network Time Protocol (NTP). The flaw exists in versions prior to 1.7.1 and is triggered when NTS is enabled on the server. An attacker can remotely send malformed NTS packets that request an excessive number of cookies, which are cryptographic tokens used in the NTS protocol to secure time synchronization. Processing these requests causes the server to allocate significantly more CPU resources than normal—approximately 2 to 4 times the typical usage—leading to degraded server performance. This resource exhaustion does not require any authentication or user interaction, making it a network-exploitable vulnerability. The vulnerability could be leveraged to conduct denial-of-service attacks against ntpd-rs servers, potentially impacting the availability of time synchronization services. Precise time synchronization is critical for many networked systems, including financial services, telecommunications, and industrial control systems. The vulnerability was publicly disclosed on February 12, 2026, with a CVSS 4.0 base score of 6.9 (medium severity). No known exploits have been reported in the wild, but the risk remains until systems are updated to version 1.7.1 or later, where the issue is fixed.

For European organizations, the impact of this vulnerability can be significant, particularly for those relying on ntpd-rs servers with NTS enabled to maintain accurate and secure time synchronization. Increased CPU usage caused by malformed NTS packets can degrade server performance, potentially leading to partial or complete denial of time synchronization services. This can disrupt time-dependent operations such as logging, authentication, transaction timestamping, and network coordination. Critical sectors such as financial institutions, telecommunications providers, energy grids, and transportation systems could experience operational disruptions or reduced reliability. Additionally, degraded time services can indirectly affect security monitoring and incident response capabilities that rely on accurate timestamps. While the vulnerability does not directly compromise confidentiality or integrity, the availability impact can have cascading effects on business continuity and regulatory compliance within Europe.

European organizations should immediately upgrade all ntpd-rs deployments to version 1.7.1 or later, where this vulnerability is fixed. If upgrading is not immediately feasible, organizations should consider disabling NTS on ntpd-rs servers as a temporary mitigation, understanding this reduces the security of time synchronization. Network-level protections such as rate limiting and filtering malformed or suspicious NTS packets can help reduce the risk of exploitation. Monitoring CPU usage patterns on ntpd-rs servers can provide early detection of potential exploitation attempts. Organizations should also review and harden firewall rules to restrict access to NTP services to trusted networks or IP ranges. Finally, integrating ntpd-rs servers into broader security monitoring and incident response workflows will help detect and respond to anomalous activity related to this vulnerability.