CISA Warns U.S. Infrastructure at Risk from Iranian-Linked Cyber Activity

Category: Critical Infrastructure Security | Industries: Critical infrastructure, Defense, Research | Source: CISA

A warning issued jointly by CISA, the FBI, NSA, and DC3 urges U.S. organizations, especially those in critical infrastructure sectors, to remain alert to potential Iranian-affiliated cyber operations. According to the alert, “despite a declared ceasefire and ongoing negotiations towards a permanent solution, Iranian-affiliated cyber actors and hacktivist groups may still conduct malicious cyber activity.” While no widespread campaign has been confirmed, U.S. Defense Industrial Base (DIB) companies—particularly those with Israeli research or defense ties—face elevated risk. Recent activity has shown these actors exploiting vulnerabilities in unpatched systems, leveraging default credentials, and using social engineering to compromise targets. The advisory stresses that internet-facing systems with poor access controls or outdated configurations are especially exposed.

CISA’s fact sheet details that Iranian-aligned groups often use techniques such as automated password guessing, cracking weak password hashes, and exploiting vulnerable operational technology (OT) systems. Previous campaigns from late 2023 through early 2024 demonstrate how the Iranian Islamic Revolutionary Guard Corps (IRGC)-linked actors successfully compromised internet-connected programmable logic controllers (PLCs) and human machine interfaces (HMIs), including those tied to U.S. organizations in the water, energy, and healthcare sectors. These efforts included “hack-and-leak” operations, web defacement, and DDoS attacks—all aimed at degrading trust and amplifying social or political messages. Additionally, these actors have partnered with criminal ransomware operators to extort victims and leak stolen data, combining financial and ideological motives.

To reduce risk, the agencies urge organizations to apply phishing-resistant multi-factor authentication (MFA), implement strong password hygiene, and disconnect unnecessary remote access to ICS/OT devices. Regular patching, restricting remote access, and monitoring for unauthorized changes are core defense strategies. Organizations are also advised to rehearse and update their incident response plans and consider the downstream impact of data leaks. “Based on the current geopolitical environment,” CISA writes, “Iranian-affiliated cyber actors may target U.S. devices and networks for near-term cyber operations.” With these warnings, U.S. critical infrastructure organizations are being called on to proactively harden their networks and remain alert to opportunistic and ideologically driven threats.