Actively exploited vulnerability
Cisco Catalyst SD-WAN Manager: vulnerability flaw under attack
CVE-2026-20245 · Cisco Catalyst SD-WAN Manager Improper Encoding or Escaping of Output Vulnerability
What is affected
Cisco Catalyst SD-WAN Manager is mostly run by companies, schools and public bodies, not on home computers. You are unlikely to have it yourself, but organisations that hold your data may. Breaches that start with flaws like this one are how personal data ends up leaked.
Cisco Catalyst SD-WAN Manager formerly SD-WAN vManage contains an improper encoding or escaping of output vulnerability. This vulnerability could allow an authenticated, local attacker to execute arbitrary commands as root by supplying a crafted file to the affected system.
What an attacker can do
This is a vulnerability flaw. It lets an attacker misuse the product in a way its maker did not intend. CISA lists it because attackers are confirmed to be using it against real systems.
- How it is reached
- Needs access to the device or a file opened on it
- Access the attacker needs
- A basic user account
- Does the victim have to do something?
- No, works without the victim doing anything
What to do
- At home: nothing to install. Keep your own devices updated and use a different password for every service, so that a breach at one organisation does not open your other accounts.
- If you administer Cisco Catalyst SD-WAN Manager at work: apply the vendor's fix or mitigation now and review logs for signs of compromise, because the flaw was being exploited before it was listed.
- If the product is past its support date and no fix exists, take it off the internet or retire it.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Vendor advisories and fixes
- sec.cloudapps.cisco.comsec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-prive
How urgent is it
CISA added this vulnerability to its Known Exploited Vulnerabilities catalogue on June 9, 2026, which means there is reliable evidence of attacks in the wild. US federal agencies must fix it by June 23, 2026, a deadline that has already passed. That deadline does not bind anyone else, but it shows how seriously the agency rates it.
The EPSS model estimates a 25% probability that this flaw will be exploited somewhere in the next 30 days. That is higher than 98% of all scored vulnerabilities.
Its CVSS severity score is 7.8 out of 10 (high), as recorded in the US National Vulnerability Database.
Technical description
A vulnerability in the CLI of Cisco Catalyst SD-WAN Controller, formerly SD-WAN vSmart, Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, and Cisco Catalyst SD-WAN Validator, formerly SD-WAN vBond, could allow an authenticated, local attacker to execute arbitrary commands as root by supplying a crafted file to the affected system. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by uploading a crafted file to the affected system. A successful exploit could allow the attacker to perform command injection attacks on an affected system and elevate their privileges as the root user. To exploit this vulnerability, the attacker must have netadmin privileges on the affected system. This would require valid credentials or exploitation of or . Cisco is not aware of successful exploitation by other methods. Cisco has observed limited cases where the exploitation of this bug resulted in a configuration change pushed to edge devices. Cisco recommends that customers upgrade to the fixed software that is documented in the that was published on May 14, 2026, and verify the configuration of the edge devices.