CVE-2021-20996: Wago 0852-0303 Firmware

Medium severity, CVSS 5.3. EPSS: 0.8% chance of exploitation in the next 30 days.

In multiple managed switches by WAGO in different versions special crafted requests can lead to cookies being transferred to third parties.

Affected products

• Wago 0852-0303 Firmware: up to and including 1.2.3.s0
• Wago 0852-1305/000-001 Firmware: up to and including 1.0.4.s0
• Wago 0852-1305 Firmware: up to and including 1.1.7.s0
• Wago 0852-1505/000-001 Firmware: up to and including 1.0.4.s0
• Wago 0852-1505 Firmware: up to and including 1.1.6.s0

Published 2021-05-13. Last modified 2026-06-17.