CVE-2021-33541 Phoenix Contact: ILC1x Industrial controllers affected by Denial-of-Service vulnerability
Remote attackers can cause a denial of service on Phoenix Contact ILC1x controllers by sending crafted packets, requiring a device restart to restore network connectivity.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-33541?
CVE-2021-33541 is a high-severity denial of service vulnerability in Phoenix Contact ILC1x, published on 25 Jun 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Phoenix Contact Classic Line Controllers ILC1x0 and ILC1x1 in all versions/variants are affected by a Denial-of-Service vulnerability. The communication protocols and device access do not feature authentication measures. Remote attackers can use specially crafted IP packets to cause a denial of service on the PLC's network communication module. A successful attack stops all network communication. To restore the network connectivity the device needs to be restarted. The automation task is not affected.
Weakness: CWE-770
Which versions are affected by CVE-2021-33541?
It affects 2 products.
Products include Phoenixcontact Ilc1x0 Firmware, Phoenixcontact Ilc1x1 Firmware.
How do I fix CVE-2021-33541?
No fix has been published for CVE-2021-33541 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2021-33541 being exploited?
There is no known exploitation of CVE-2021-33541 in the wild and no public exploit code.
Sources
Also known as GHSA-jwj9-vx74-vv26.