CISA Warns of Cyberattacks on Water Utilities

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has issued a warning indicating a significant rise in cyberattacks on internet-exposed programmable logic controllers (PLCs) in the water and wastewater sector. These attacks could potentially disrupt operations at water utilities and jeopardize public safety. CISA reported that attacks have increased in recent months, particularly targeting systems that are not adequately secured. The agency emphasized that many of these PLCs are accessible via the internet, making them an attractive target for cybercriminals.

Attackers could exploit these vulnerabilities to manipulate critical infrastructures. Some of the affected systems are responsible for monitoring and controlling water treatment and wastewater facilities. CISA pointed out that the attacks aim not only to destroy data but also to take control of the systems. This could lead to serious disruptions in water supply. The agency recommends that water utility operators regularly check their systems for vulnerabilities and ensure that all security updates are installed promptly.

Furthermore, they should ensure that their systems are not unnecessarily connected to the internet to minimize the risk of an attack. CISA has also published specific guidelines to enhance the security of PLCs. Another aspect of the warning concerns the need for training staff to raise awareness of cyber threats. CISA highlights that human error often represents one of the biggest vulnerabilities in cybersecurity. Therefore, it is crucial that employees are able to recognize suspicious activities and respond appropriately.

CISA has also stressed that collaboration between various agencies and companies is essential to ensure the security of critical infrastructure. A coordinated approach can help detect and respond to threats early. The agency has called for sharing information about cyber incidents to improve responsiveness. The warning comes at a time when the U.S. must increasingly respond to cyberattacks that have risen in recent years. According to an FBI report, there was a 30% increase in cyber incidents in 2025 compared to the previous year.

This development underscores the need to strengthen security measures in critical infrastructures. CISA plans to launch additional training programs and information campaigns in the coming months to inform water utility operators about the latest threats and security practices. These initiatives aim to enhance the resilience of water infrastructure against cyberattacks. The agency has already collaborated with several water utilities to develop tailored security solutions. CISA has also pointed out that the threat of cyberattacks is not limited to water utilities but also affects other critical infrastructures such as energy supply and transportation.

Therefore, the agency has called for a comprehensive approach to improving cybersecurity across all sectors. Collaboration between different sectors is seen as key to strengthening national security. CISA has urged water utility operators to review their security protocols and ensure they meet current standards. This includes implementing multi-factor authentication procedures and regularly conducting security audits. The agency has emphasized that proactive measures are crucial to fend off potential attacks.

CISA's warning is another indication of the growing challenges in the field of cybersecurity. Given the increasing complexity and frequency of cyberattacks, it is essential that all stakeholders, including government, industry, and the public, work together to ensure the security of critical infrastructures. CISA has announced that it will regularly provide updates on threats and security measures. The warning was issued on July 30, 2026, and urges all operators of water and wastewater systems to take immediate action to protect their systems.