Security Experts:

Connect with us

Hi, what are you looking for?

SecurityWeekSecurityWeek

Data Protection

Severe Vulnerabilities Expose MicroLogix PLCs to Attacks

Rockwell Automation has released patches and mitigations for several potentially serious vulnerabilities discovered by Cisco Talos researchers in its Allen-Bradley MicroLogix 1400 programmable logic controllers (PLCs).

Rockwell Automation has released patches and mitigations for several potentially serious vulnerabilities discovered by Cisco Talos researchers in its Allen-Bradley MicroLogix 1400 programmable logic controllers (PLCs).

According to Cisco Talos, the vulnerabilities can be exploited for denial-of-service (DoS) attacks, modifying a device’s configuration and ladder logic, and writing or removing data on its memory module.

Since these controllers are typically used in industrial environments, including in critical infrastructure organizations, exploitation of the flaws could result in significant damage, Talos said.Vulnerabilities found in MicroLogix controllers

The most serious of the flaws, based on their CVSS score of 10, are a series of access control issues that have been assigned a dozen CVE identifiers. A remote and unauthenticated attacker can exploit these vulnerabilities to obtain sensitive information, modify a device’s settings, or change its ladder logic – all by sending specially crafted packets.

While exploiting many of these flaws requires that the controller’s keyswitch is in REMOTE or PROG position, reading the master password and the master ladder logic works regardless of the keyswitch setting.

Learn More at SecurityWeek’s ICS Cyber Security Conference

Another potentially serious flaw is CVE-2017-12088, which allows a remote attacker to cause the controller to enter a fault state and potentially delete ladder logic by sending specially crafted packets to the Ethernet port.

DoS vulnerabilities also exist in the device’s program download and firmware update functionality, but these have been assigned only a “medium severity” rating.

Other issues considered less serious include a file-write vulnerability affecting a memory module, and a DoS flaw related to the session connection functionality.

While a CVE identifier has been assigned to the session communication bug, Rockwell says the system actually works as intended and no patches or mitigations are required.

Rockwell Automation has released firmware updates that address some of these flaws. The company has also proposed a series of mitigations that include migrating to more recent series of the MicroLogix 1400 controller, setting the keyswitch to “Hard Run” to prevent unauthorized changes to the device, and disabling impacted services.

Cisco has published technical details and proof-of-concept (PoC) code for each of the vulnerabilities. Rockwell Automation has also released an advisory, but it can only be accessed by registered users.

This is not the first time Cisco Talos researchers have found vulnerabilities in MicroLogix 1400 PLCs. In 2016, they reported discovering a weakness that could have been exploited to modify the firmware on these devices.

Related: Rockwell Automation Patches Serious Flaw in MicroLogix 1400 PLC

Related: Several Vulnerabilities Found in Rockwell Automation PLCs

Related: Flaws in Rockwell PLCs Expose Operational Networks

Written By

Eduard Kovacs (@EduardKovacs) is a contributing editor at SecurityWeek. He worked as a high school IT teacher for two years before starting a career in journalism as Softpedia’s security news reporter. Eduard holds a bachelor’s degree in industrial informatics and a master’s degree in computer techniques applied in electrical engineering.

Click to comment

Daily Briefing Newsletter

Subscribe to the SecurityWeek Email Briefing to stay informed on the latest threats, trends, and technology, along with insightful columns from industry experts.

Join this webinar to learn best practices that organizations can use to improve both their resilience to new threats and their response times to incidents.

Register

Join this live webinar as we explore the potential security threats that can arise when third parties are granted access to a sensitive data or systems.

Register

Expert Insights

Related Content

Application Security

Cycode, a startup that provides solutions for protecting software source code, emerged from stealth mode on Tuesday with $4.6 million in seed funding.

Vulnerabilities

Less than a week after announcing that it would suspended service indefinitely due to a conflict with an (at the time) unnamed security researcher...

Data Protection

The CRYSTALS-Kyber public-key encryption and key encapsulation mechanism recommended by NIST for post-quantum cryptography has been broken using AI combined with side channel attacks.

Data Protection

The cryptopocalypse is the point at which quantum computing becomes powerful enough to use Shor’s algorithm to crack PKI encryption.

Risk Management

The supply chain threat is directly linked to attack surface management, but the supply chain must be known and understood before it can be...

Vulnerabilities

Apple has released updates for macOS, iOS and Safari and they all include a WebKit patch for a zero-day vulnerability tracked as CVE-2023-23529.

Vulnerabilities

Patch Tuesday: Microsoft warns vulnerability (CVE-2023-23397) could lead to exploitation before an email is viewed in the Preview Pane.

Application Security

Drupal released updates that resolve four vulnerabilities in Drupal core and three plugins.