Cisco has patched a flaw in Catalyst SD-WAN Manager (formerly vManage), the console used to manage thousands of SD-WAN devices, that attackers were already exploiting as a zero-day to gain root. The bug (CVE-2026-20262) stems from weak validation of file uploads in the web interface, letting an authenticated low-privilege remote attacker create or overwrite any file on the system by sending crafted HTTP requests, and from there run commands as root. It affects every deployment type, including on-premises, Cisco-managed cloud, and the FedRAMP government edition, regardless of configuration. It is the latest in a run of exploited Cisco SD-WAN Manager zero-days this year.
Cisco has warned of an actively exploited, unpatched zero-day in Cisco Catalyst SD-WAN Manager (CVE-2026-20245) that enables root privilege escalation across all deployment types, including on-prem, Cloud, Managed, and FedRAMP Government. The flaw stems from insufficient validation of user-supplied input: an attacker who uploads a crafted file can perform command injection and run arbitrary commands as root. Exploitation requires netadmin privileges - obtained via valid credentials or by chaining CVE-2026-20182 or CVE-2026-20127. Mandiant reported the activity to Cisco's PSIRT in June. Cisco has observed limited cases where exploitation pushed configuration changes to edge devices, and published IoCs pointing to suspicious tenant-list uploads in scripts.log.
CISA added a Cisco Catalyst SD-WAN Manager information disclosure flaw to its Known Exploited Vulnerabilities catalog on Monday, ordering federal agencies to patch by Friday, April 24 - an unusually aggressive 4-day deadline that reflects confirmed active exploitation. CVE-2026-20133 is an unauthenticated remote flaw in the SD-WAN Manager (formerly vManage) API, caused by insufficient file system access restrictions. An attacker can access the API and read sensitive information from the underlying operating system - including credentials that enable follow-on attacks. Cisco patched it in late February alongside two other SD-WAN Manager flaws (CVE-2026-20128 and CVE-2026-20122, both also added to KEV this week and confirmed exploited in the wild). Catalyst SD-WAN Manager is used to centrally manage up to 6,000 SD-WAN devices from one dashboard, making it a high-value target. Oddly, Cisco's PSIRT still says they have no evidence of public exploitation - contradicting CISA. CISA is treating its own intelligence as authoritative and has issued Emergency Directive 26-03 plus a Hunt & Hardening Guide for Cisco SD-WAN. Over the past several years CISA has tagged 91 Cisco vulnerabilities as exploited in the wild, six used by ransomware operations.