CVE-2026-20128
Cisco Catalyst SD-WAN Manager Storing Passwords in a Recoverable Format Vulnerability
Cisco Catalyst SD-WAN Manager
A vulnerability in the Data Collection Agent (DCA) feature of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to gain DCA user privileges on an affected system. This vulnerability is due to the presence of a credential file for the DCA user on an affected system. An attacker could exploit this vulnerability by sending a crafted HTTP request and reading the file that contains the DCA password from that affected system. A successful exploit could allow the attacker to access another affected system and gain DCA user privileges. Note: Cisco Catalyst SD-WAN Manager releases 20.18 and later are not affected by this vulnerability.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 20 April 2026. US federal agencies were required to remediate it by 23 April 2026.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 8.3%, which is higher than 95% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
Frequently asked questions
Is CVE-2026-20128 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2026-20128.
What does CVE-2026-20128 affect?
CVE-2026-20128 affects Cisco Catalyst SD-WAN Manager. A vulnerability in the Data Collection Agent (DCA) feature of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to gain DCA user privileges on an affected system. This vulnerability is due to the presence of a credential file for the DCA user on an affected system. An attacker could exploit this vulnerability by sending a crafted HTTP request and reading the file that contains the DCA password from that affected system. A successful exploit could allow the attacker to access another affected system and gain DCA user privileges. Note: Cisco Catalyst SD-WAN Manager releases 20.18 and later are not affected by this vulnerability.
How severe is CVE-2026-20128?
CVE-2026-20128 is rated HIGH with a CVSS base score of 7.5. EPSS puts the probability of exploitation in the next 30 days at 8.3%, higher than 95% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 23 April 2026.
How should organisations respond to CVE-2026-20128?
Apply the vendor patch for Cisco Catalyst SD-WAN Manager as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.