Cisco is warning that a critical authentication bypass vulnerability in Cisco Catalyst SD-WAN, tracked as CVE-2026-20127, was actively exploited in zero-day attacks that allowed remote attackers to compromise controllers and add malicious rogue peers to targeted networks.
https://www.bleepingcomputer.com/news/security/critical-cisco-sd-wan-bug-exploited-in-zero-day-attacks-since-2023/

Critical Cisco SD-WAN bug exploited in zero-day attacks since 2023
Cisco is warning that a critical authentication bypass vulnerability in Cisco Catalyst SD-WAN, tracked as CVE-2026-20127, was actively exploited in zero-day attacks that allowed remote attackers to compromise controllers and add malicious rogue peers to targeted networks.
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