CVE-2025-41706: Phoenix Contact: Webserver Denial of Service through Malformed Content-Length

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-10-14 · updated 2026-10-18
Weakness: CWE-120

Description

The webserver is vulnerable to a denial of service condition. An unauthenticated remote attacker can craft a special GET request with an over-long content-length to trigger the issue without affecting the core functionality.

Affected products

Phoenix Contact QUINT4-UPS/24DC/24DC/10/EIP: from VC:00 before VC:07 — fixed in VC:07
Phoenix Contact QUINT4-UPS/24DC/24DC/20/EIP: from VC:00 before VC:07 — fixed in VC:07
Phoenix Contact QUINT4-UPS/24DC/24DC/40/EIP: from VC:00 before VC:07 — fixed in VC:07
Phoenix Contact QUINT4-UPS/24DC/24DC/5/EIP: from VC:00 before VC:07 — fixed in VC:07

How to fix

Upgrade to a fixed version: Phoenix Contact QUINT4-UPS/24DC/24DC/10/EIP VC:07; Phoenix Contact QUINT4-UPS/24DC/24DC/20/EIP VC:07; Phoenix Contact QUINT4-UPS/24DC/24DC/40/EIP VC:07; Phoenix Contact QUINT4-UPS/24DC/24DC/5/EIP VC:07. Check the vendor advisory for mitigations.

References

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