CISA red teams fully compromised two critical infrastructure orgs. One SOC isolated hosts in minutes; the other never detected the breach.

CISA published an advisory (AA26-237A) documenting two simultaneous red team assessments at critical infrastructure organizations. Both organizations lost full domain control and had their cloud environments compromised. One of them didn’t know until CISA told them afterward.

“The Cybersecurity and Infrastructure Security Agency (CISA) conducted simultaneous red team assessments at two organizations and observed different defensive outcomes. In both environments, the red team achieved full domain compromise and accessed sensitive business systems (SBSs) and cloud resources.” states CISA. “Organization A failed to detect or contain the activity, but Organization B rapidly identified initial compromise attempts, isolated affected systems, and forced the red team into an assume breach model.”

Organization A is a Government Services and Facilities Sector entity. Organization B operates in the Water and Wastewater Systems Sector. The red team used comparable techniques against both. The difference in outcome was entirely about detection and response, not the sophistication of the attack.

At Organization A, the red team found a web application that still used default credentials. They used it to send phishing emails from a trusted internal address and gained access to four workstations. From there, they exploited a misconfigured Active Directory Certificate Services template with the ESC1 flaw. This allowed a low-privileged user to request certificates for other users, including administrators. They then reached all the targeted sensitive business systems without anyone noticing. After moving into the cloud, they even read SOC staff emails to see if the attack had been detected. It hadn’t.

“Without well-defined baselines and alert filtering, false positives and routine alerts overwhelm defenders, obscuring real threats.” CISA continues. “Organizations that tune alerts to highlight anomalies and filter out normal business activity enable defenders to focus on genuine incidents and respond rapidly.”

Organization A’s SOC was receiving thousands of false positive alerts, many at higher severity than the actual intrusion alerts the red team was generating. Staff eventually reviewed SCCM-related alerts from real red team activity, couldn’t identify the system’s owner or function, and marked it a false positive.

The red team confirmed the miss by reading SOC email. Then they used keyloggers and screenshot capture on SOC workstations to make sure nothing was coming. Nothing was. The organization had multiple separate SOCs with different EDR solutions and no cross-team visibility, which meant that even if one team noticed something, there was no mechanism to act on it across the relevant systems.

“Detection tools are only as effective as the people, processes, and procedures supporting them. SOC staff should not operate in silos and should have clear authority unhindered by bureaucracy to effectively contain and resolve incidents.” add CISA.

At Organization A, SOC analysts were managing systems they didn’t fully understand and had no written escalation procedures, so their default response to ambiguity was to wait. At Organization B, staff triaged, investigated, coordinated with engineering, and reimaged machines before handing them back to users.

At Organization B, the red team still found important security gaps. They discovered a password stored in plain text inside an XML file on an SCCM distribution point. They used the related service account to gain powerful rights over a domain controller and then performed a DCSync attack, obtaining the krbtgt hash. This allowed them to create Golden Tickets and impersonate users across the domain.

They also found a path into the OT network through RDP files pointing to a bastion host. Using FTP credentials found on a jump server, they connected to the bastion through SSH. The bastion had no outbound internet access, so their payload could not run, and the SOC quarantined the host. Still, the access path was there.

Both organizations also had the same cloud security problem: neither had enabled Conditional Access for workload identities. This Microsoft feature applies access controls to applications and service accounts, not just human users. Without it, applications with broad Microsoft Graph permissions can bypass normal Conditional Access rules. CISA’s red team used this gap in both organizations to access emails across the companies.

In Organization A, the team also found AWS IAM credentials stored in users’ home directories with no expiration date. Those credentials could remain valid indefinitely, creating another long-term risk.

In Organization B’s cloud environment, the red team abused Seamless SSO by using Kerberos tickets obtained via DCSync to authenticate to Azure without needing any user’s cleartext password. They found a disabled AD-synced account that owned an application with permission to read, write, and send emails for every user in the tenant. They re-enabled the account, DCSynced its credentials, added a client secret to the application, and could then access the full mailbox of every employee from the public internet. Organization B’s detections flagged the AzureHound tool by user agent and caught anomalous Microsoft Graph API request volumes, but those controls arrived after the initial cloud access was already established.

CISA recommends several practical steps to improve security. These include hardening ADCS by disabling CT_FLAG_ENROLLEE_SUPPLIES_SUBJECT on templates and limiting who can enroll, setting the Machine Account Quota to zero when there is no operational need, and removing cleartext credentials from workstations and network shares.

Organizations should also enable Conditional Access for workload identities, create procedures to revoke tokens, and treat SCCM and similar endpoint management platforms as Tier 0 assets, giving them the same level of protection as domain controllers.

The full advisory also maps each red team technique to its MITRE ATT&CK identifier and compares how well the two organizations detected the different stages of the attacks.

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Pierluigi Paganini

(SecurityAffairs – hacking, CISA)

NSA, CISA, FBI, DOE, and EPA warn of active AI-assisted attacks against Siemens S7 PLCs across US critical infrastructure sectors.

Five U.S. federal agencies issued a joint advisory this week warning of an active hacking campaign against Siemens S7 Series programmable logic controllers. The advisory, CISA AA26-231A, is co-signed by NSA, FBI, DOE, and EPA and covers every S7 generation, from the S7-200 to the S7-1500 F-series safety controllers.

The advisory is direct about one thing from the first paragraph: this is not a theoretical risk.

“The threat actors are conducting reconnaissance and capability development against U.S.-based Siemens PLC installations using AI-generated exploitation scripts disguised as legitimate monitoring tools. The actors leverage Internet scanning services to find Internet-exposed PLCs running outdated software or that are otherwise poorly protected.” reads the advisory. “The U.S. critical infrastructure sectors most targeted by this threat activity include Critical Manufacturing, Energy, Water and Wastewater, Chemical, Food and Agriculture, and Commercial Facilities. This is not a theoretical risk—it is an active threat. “

The key detail is how the attackers try to hide their activity. They make their scripts look like legitimate OT monitoring software, making it harder for security teams to notice them while they map the target environment.

The tools themselves are not custom malware. The attackers use the open-source snap7.dll and python-snap7 libraries, which are legitimate industrial automation tools. These libraries can communicate directly with Siemens PLCs over S7comm on TCP port 102, allowing access to PLC memory, configuration data and ladder logic programs.

“Using AI to generate exploitation scripts represents an evolution in threat actor capabilities, dramatically reducing the technical expertise and time required to develop working ICS exploitation scripts and malicious tools. In addition, AI enables adversaries to rapidly leverage additional attack vectors and adapt to defensive measures.” continues the advisory. “Threat actors can easily collect public information about vulnerabilities and weaknesses, find exposed and exploitable PLCs, and use AI-generated scripts to act on that information. If PLCs are exposed to the Internet, they are at high risk for exploitation.”

Researchers warn that a defender who patches a vulnerability may now find the attacker’s tooling already adapted before the change window closes.

The observed activity breaks into two phases. Actors use scanning services like Censys and ZoomEye to locate Internet-exposed PLCs, then run read operations to understand the target environment before any writes happen. The authoring agencies assess this as pre-positioning: the actors are building a map and testing their techniques against specific CPU models, refining as they go, before they’re ready to cause disruption.

The target list covers Critical Manufacturing, Energy, Water and Wastewater, Chemical, Food and Agriculture, and Commercial Facilities. The Defense Industrial Base is also named, given its use of S7-series hardware. If these actors move from read to write, the potential consequences include process disruption, equipment damage, and safety incidents through manipulation of interlocks or emergency shutdown systems, and cascading effects across interconnected supply chains.

The advisory flags third-party exposure as a specific problem. Asset owners who rely on system integrators or managed service providers for remote PLC access may not know their controllers are reachable from the Internet. If an external support partner holds credentials for your S7 devices and you haven’t recently verified that those connections are segmented and monitored, this advisory is a good prompt to check.

There are several clear signs defenders can monitor. They should look for S7comm connections from devices that are not normally used for engineering, PLC read or write activity outside scheduled maintenance, and scans of multiple IP addresses on TCP port 102. It is also worth checking for Python processes loading snap7.dll on systems where it should not be present. Connections from unexpected countries or locations should also raise an alert.

On the mitigation side, the agencies prioritize inventory first, then patching with Internet-facing controllers at the top of the queue. Block TCP port 102 at the perimeter firewall, require password protection on all controllers, configure protection levels to limit what an unauthenticated or low-privilege session can read or write, and deploy ICS-aware monitoring capable of baselining legitimate S7comm behavior. Disabling the PLC web server where it’s not needed and limiting simultaneous S7comm sessions also appear in the guidance, alongside TIA Portal’s know-how protection and complete restart protection features.

The advisory closes by recommending direct engagement with Siemens ProductCERT for model-specific hardening and patch compatibility verification, which matters in OT environments where a firmware update can interact badly with third-party integrations and can’t simply be rolled back.

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Pierluigi Paganini

(SecurityAffairs – hacking, CISA)

Iran-linked hackers targeted Water Infrastructure in New Jersey and Alabama, bringing confirmed attacks to at least 12 states, with limited disruption.

The wave of cyberattacks targeting US water infrastructure has reached New Jersey and Alabama, bringing the confirmed count to at least 12 states since late July. The attacks are linked to Iranian hackers targeting industrial control systems made by Rockwell Automation and potentially other major vendors. Minnesota was the first to confirm over 30 affected water systems, followed by Michigan, South Dakota, and Georgia, and now two more states.

“The City of Cape May Sewer Department and the Borough of Woodbine Water Department reported the attacks on Thursday. Officials said the attacks happened nearly simultaneously early in the morning on July 27.” reports Fox29 “Both systems were impacted for approximately 12 hours.”

Water kept running in both New Jersey districts throughout the incident, and tests afterward confirmed no impact on water quality or safety. Cape May city manager Paul Dietrich told Fox29 that hackers changed settings to prevent remote access to the system, but did not take control of the systems to do anything — which is a meaningful distinction, and not the kind anyone wants to be making about their water supply.

“Cybersecurity experts say hackers could control a lot after breaking into a local water system. ‘They’re actually having the ability to control the water pressure, meaning that they could increase the pressure and cause flooding, or they could decrease the pressure so that you would have a reduced pressure, or ultimately, have no water flow at all,’ said Ian Marlow, CEO of FITECH.” continues Fox29.

In Alabama, the Childersburg Water, Sewer and Gas system was hit the same day, July 27, with hackers targeting industrial control systems. The attack didn’t disrupt water services there either. Neither department’s customer data was accessed in New Jersey, and no significant service disruption was reported in Alabama.

“The Childersburg Water, Sewer, and Gas Board reported that its computerized monitoring and control network was targeted in a cyberattack late last month, prompting officials to temporarily disconnect the system while additional safeguards are put in place.” reports Sylacauga News. “According to the utility, the incident occurred on Monday, July 27 and involved a programmable logic controller, a type of industrial device used to help manage utility operations. Officials said the attack was part of a broader effort that also targeted several other public utilities.”

The pattern across all confirmed states is consistent: attacks targeted operational technology and industrial control systems, some facilities shut down systems as a precaution, disruptions were limited, and drinking water remained safe in every case. The FBI confirmed at least seven states had been targeted as of July 30. Wisconsin, Pennsylvania, and Washington have issued warnings to water utilities without confirming attacks. New York has not said whether its utilities were hit but announced more than $9 million in grants to strengthen water sector cybersecurity.

The practical lesson from every confirmed case so far is the same one CISA has been repeating since its July 30 alert: get PLCs and industrial control systems off direct internet exposure, because the attackers are scanning for exactly that exposure and finding it.

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Pierluigi Paganini

(SecurityAffairs – hacking, Water Infrastructure)