PHOENIX CONTACT FL SWITCH 3xxx/4xxx/48xx series web-service authentication bypass

VDE-2017-006 (2018-01-10 10:36 UTC+0200)

Affected Vendors


Affected Products


Vulnerability Type

Gain Privilege


PHOENIX CONTACT FL SWITCH 3xxx series, FL SWITCH 4xxx series, and FL SWITCH 48xx series products running firmware version 1.0 to 1.32 allow unauthenticated users with network access to gain administrative privileges (CVE-2017-16743) and expose information to unauthenticated users in Monitor Mode (CVE-2017-16741).


CVE-2017-16743: web-service authentication bypass, improper authorization (CWE-285)

By crafting HTTP Set-Cookie and POST requests, an unauthenticated attacker with network access may bypass the web-service authentication and gain administrative privileges on the managed switch devices.

CVE-2017-16741: information exposure (CWE-200)

Any user with network access to a managed switch device may use Monitor Mode to read diagnostic information from the device's web interface without prior authentication in the web GUI. This includes information about model, subnet mask, uptime, and utilisation.


Customers using PHOENIX CONTACT FL SWITCH 3xxx series, FL SWITCH 4xxx series and FL SWITCH 48xx series devices with firmware versions up to 1.32 are recommended to update to firmware version 1.33 or higher, which fixes these vulnerabilities. The updated firmware may be downloaded from the following managed switch product pages on the vendor's website:

Article No.

Model Updated Firmware
2891030 FL SWITCH 3005
2891032 FL SWITCH 3005T
2891033 FL SWITCH 3004T-FX
2891034 FL SWITCH 3004T-FX ST
2891031 FL SWITCH 3008
2891035 FL SWITCH 3008T
2891036 FL SWITCH 3006T-2FX
2891037 FL SWITCH 3006T-2FX ST
2891067 FL SWITCH 3012E-2SFX
2891066 FL SWITCH 3016E
2891058 FL SWITCH 3016
2891059 FL SWITCH 3016T
2891060 FL SWITCH 3006T-2FX SM
2891062 FL SWITCH 4008T-2SFP
2891061 FL SWITCH 4008T-2GT-4FX SM
2891160 FL SWITCH 4008T-2GT-3FX SM
2891073 FL SWITCH 4808E-16FX LC-4GC
2891080 FL SWITCH 4808E-16FX SM-4GC
2891086 FL SWITCH 4808E-16FX SM ST-4GC
2891085 FL SWITCH 4808E-16FX ST-4GC
2891079 FL SWITCH 4808E-16FX-4GC
2891074 FL SWITCH 4808E-16FX SM LC-4GC
2891063 FL SWITCH 4012T 2GT 2FX
2891161 FL SWITCH 4012T-2GT-2FX ST
2891072 FL SWITCH 4824E-4GC
2891102 FL SWITCH 4800E-24FX-4GC
2891104 FL SWITCH 4800E-24FX SM-4GC
2891120 FL SWITCH 3012E-2FX
2891119 FL SWITCH 3012E-2FX SM
2891162 FL SWITCH 4000T-8POE-2SFP-R please contact your local customer service

Reported by

Ilya Karpov and Evgeniy Druzhinin (Positive Technologies) reported these vulnerabilities to PHOENIX CONTACT.