# What is CVE-2012-6435?

> CVE-2012-6435 is a high-severity flaw (CVSS 7.5) in Controllogix Controllers from Rockwellautomation, published on 24 January 2013. It is not on the list of flaws known to be exploited today. The latest forecast puts its chance of use in the next 30 days at 33%. If you run an affected version, plan in the vendor’s fix.

Canonical page: https://www.precursorintelligence.com/what-is/cve-2012-6435

## At a glance

- **Verdict:** Fix this soon. Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month.
- **Precursor Intelligence risk score:** 46 out of 100 (Medium); action: Plan remediation. Kept up to date as the evidence changes.
- **Severity:** High (CVSS 7.5 out of 10)
- **Known to be exploited:** No, not on the list of flaws known to be exploited today
- **Chance of use in the next 30 days:** 33% (latest exploit-likelihood forecast)
- **Published:** 24 January 2013
- **Record last updated:** 16 June 2026
- **Main product:** Controllogix Controllers from Rockwellautomation
- **Affected products:** 17

## What is CVE-2012-6435? In plain terms

It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can take it offline.

### The official description

When an affected product receives a valid CIP message from an unauthorized or unintended source to Port 2222/TCP, Port 2222/UDP, Port 44818/TCP, or Port 44818/UDP that instructs the CPU to stop logic execution and enter a fault state, a DoS can occur. This situation could cause loss of availability and a disruption of communication with other connected devices.

Rockwell Automation EtherNet/IP products; 1756-ENBT, 1756-EWEB, 1768-ENBT, and 1768-EWEB communication modules; CompactLogix L32E and L35E controllers; 1788-ENBT FLEXLogix adapter; 1794-AENTR FLEX I/O EtherNet/IP adapter; ControlLogix 18 and earlier; CompactLogix 18 and earlier; GuardLogix 18 and earlier; SoftLogix 18 and earlier; CompactLogix controllers 19 and earlier; SoftLogix controllers 19 and earlier; ControlLogix controllers 20 and earlier; GuardLogix controllers 20 and earlier; and MicroLogix 1100 and 1400

### What kind of flaw is it?

- CWE-284: Improper Access Control

### How an attack on it works

- Where an attacker can be: Anywhere on the internet
- How hard it is to pull off: Easy: no special conditions
- Login needed first: No login needed
- Does someone have to click: No, nobody has to do anything
- What an attacker gets: Can take it offline

Severity vector: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`

## Is CVE-2012-6435 being exploited? Not that we know of

It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 33%. That can change at any time, which is why we keep watching.

Exploit likelihood over the last 7 days: 33%, 33%, 33%, 33%, 33%, 33%, 33%.

### Timeline

- 24 January 2013: Published
- 27 November 2025: Exploit likelihood fell
- 16 June 2026: Exploit likelihood jumped
- 16 June 2026: Record last updated

### How Precursor Intelligence ranks it

CVE-2012-6435 scores **46 out of 100 (Medium)**, with the action "Plan remediation".

Every published flaw gets a risk score from 0 to 100, kept up to date as the evidence changes. Four things go into the score, from the one that counts most to the ones that count less:

- Evidence it is being exploited: biggest factor
- How severe it is: strong factor
- How widely exposed it is: smaller factor
- Threat activity around it: smaller factor

85 and above is Critical. Anything confirmed as exploited is always marked for an emergency patch, whatever its score. When this flaw matches software you track, it lands in your list with its score and the reasons behind it.

## Who is affected by CVE-2012-6435?

The published record lists 17 products.

- [Controllogix Controllers](https://www.precursorintelligence.com/product/rockwellautomation/controllogix_controllers) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Application): up to 20
- [Micrologix](https://www.precursorintelligence.com/product/rockwellautomation/micrologix) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Application): up to 1100, up to 1400
- [1756-Enbt](https://www.precursorintelligence.com/product/rockwellautomation/1756-enbt) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): version not specified
- [1756-Eweb](https://www.precursorintelligence.com/product/rockwellautomation/1756-eweb) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): version not specified
- [1768-Enbt](https://www.precursorintelligence.com/product/rockwellautomation/1768-enbt) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): version not specified
- [1768-Eweb](https://www.precursorintelligence.com/product/rockwellautomation/1768-eweb) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): version not specified
- 1794-Aentr Flex I/o Ethernet/ip Adapter by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): version not specified
- [Compactlogix](https://www.precursorintelligence.com/product/rockwellautomation/compactlogix) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): up to 18
- [Compactlogix Controllers](https://www.precursorintelligence.com/product/rockwellautomation/compactlogix_controllers) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): up to 19
- [Compactlogix L32e Controller](https://www.precursorintelligence.com/product/rockwellautomation/compactlogix_l32e_controller) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): version not specified
- [Compactlogix L35e Controller](https://www.precursorintelligence.com/product/rockwellautomation/compactlogix_l35e_controller) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): version not specified
- [Controllogix](https://www.precursorintelligence.com/product/rockwellautomation/controllogix) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): up to 18
- [Flexlogix 1788-Enbt Adapter](https://www.precursorintelligence.com/product/rockwellautomation/flexlogix_1788-enbt_adapter) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): version not specified
- [Guardlogix](https://www.precursorintelligence.com/product/rockwellautomation/guardlogix) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): up to 18
- [Guardlogix Controllers](https://www.precursorintelligence.com/product/rockwellautomation/guardlogix_controllers) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Application): up to 20
- [Softlogix](https://www.precursorintelligence.com/product/rockwellautomation/softlogix) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Hardware): up to 18
- [Softlogix Controllers](https://www.precursorintelligence.com/product/rockwellautomation/softlogix_controllers) by [Rockwellautomation](https://www.precursorintelligence.com/vendors/rockwellautomation) (Application): up to 19

## How do I fix CVE-2012-6435?

1. **Check whether you run it.** Compare your versions with the affected products above. Not sure what you run? Precursor Intelligence can work it out from your public website, or you can pick it from a list.
2. **Apply the vendor’s fix.** Install the latest update from the vendor. The references list where the vendor has published details.
3. **If you can’t patch today.** Follow any mitigation the vendor publishes, and limit who can reach the affected system from the internet until the update is in.
4. **Keep an eye on it.** Track the product and we tell you as soon as we spot this flaw on the list of exploited flaws, or a jump in its exploit likelihood.

### References

- [rockwellautomation.custhelp.com](http://rockwellautomation.custhelp.com/app/answers/detail/a_id/54102)
- [rockwellautomation.custhelp.com](https://rockwellautomation.custhelp.com/app/answers/detail/a_id/470154)
- [rockwellautomation.custhelp.com](https://rockwellautomation.custhelp.com/app/answers/detail/aid/470155)
- [rockwellautomation.custhelp.com](https://rockwellautomation.custhelp.com/app/answers/detail/aid/470156)
- [cisa.gov](https://www.cisa.gov/news-events/ics-advisories/icsa-13-011-03)
- [us-cert.gov](http://www.us-cert.gov/control_systems/pdf/ICSA-13-011-03.pdf) (Government resource)

## Questions

### What is CVE-2012-6435?

CVE-2012-6435 is a high-severity flaw in Controllogix Controllers from Rockwellautomation, published on 24 January 2013. It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can take it offline.

### How serious is CVE-2012-6435?

It scores 7.5 out of 10 on the CVSS severity scale, which is high. Our risk score for CVE-2012-6435 is 46 out of 100, which is Medium. Its action is "Plan remediation". Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month.

### Is CVE-2012-6435 being exploited?

It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 33%. That can change at any time, which is why we keep watching.

### Which versions does CVE-2012-6435 affect?

For Controllogix Controllers from Rockwellautomation: up to 20. The record lists 17 products in all, each with its versions, under "Who is affected" on this page.

### How do I fix CVE-2012-6435?

Install the update the vendor names in its advisory. If you can't patch today, follow the vendor's mitigation and limit who can reach the affected system from the internet.

## Does CVE-2012-6435 affect you?

Precursor Intelligence keeps checking for you:

- **Tell us what you run.** Pick your software from a list, or let us work it out from your website.
- **We match it to every flaw.** Over 400,000 published flaws, checked against your list.
- **Ranked by real-world risk.** Every flaw gets a 0 to 100 risk score, kept up to date, led by evidence criminals are using it.
- **Told as soon as we know.** An alert by email, in the app or by webhook to your own tools.

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