CVE-2021-33541

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.

• CWE-770

• https://cert.vde.com/en-us/advisories/vde-2021-019Third Party Advisory
• https://cert.vde.com/en-us/advisories/vde-2021-019Third Party Advisory

Published

Jun 25, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2021-33535In Weidmueller Industrial WLAN devices in multiple versions …8.8
• CVE-2021-33536In Weidmueller Industrial WLAN devices in multiple versions …7.5
• CVE-2021-33537In Weidmueller Industrial WLAN devices in multiple versions …8.8
• CVE-2021-33538In Weidmueller Industrial WLAN devices in multiple versions …8.8
• CVE-2021-33539In Weidmueller Industrial WLAN devices in multiple versions …7.2
• CVE-2021-33540In certain devices of the Phoenix Contact AXL F BK and IL BK…7.3
• CVE-2021-33542Phoenix Contact Classic Automation Worx Software Suite in Ve…7
• CVE-2021-33543Multiple camera devices by UDP Technology, Geutebrück and ot…9.8
• CVE-2021-33544Multiple camera devices by UDP Technology, Geutebrück and ot…7.2
• CVE-2021-33545Multiple camera devices by UDP Technology, Geutebrück and ot…7.2
• CVE-2021-33546Multiple camera devices by UDP Technology, Geutebrück and ot…7.2
• CVE-2021-33547Multiple camera devices by UDP Technology, Geutebrück and ot…7.2