EXECUTIVE SUMMARY:
CVE-2026-20262 with a CVSS score of 6.5 is a critical arbitrary file write vulnerability affecting Cisco Catalyst SD‑WAN Manager (formerly SD‑WAN vManage) across all versions and deployment types. The flaw resides in the web UI file‑upload function, where user‑supplied input is not properly validated, allowing an authenticated attacker with at least write privileges to send a crafted HTTP request to the vulnerable API endpoint and specify a path‑traversal payload. By exploiting this vector, the attacker can create or overwrite any file on the underlying operating system, such as deploying a malicious WAR file into the WildFly deployment directory, which can later be executed to gain root‑level code execution. Business impact includes potential full system compromise, loss of confidentiality, integrity, and availability of the SD‑WAN management plane, and the ability for the adversary to pivot to other network components. Exploitation requires valid credentials and network access to the manager's web interface; systems exposed to the internet with open ports are especially at risk. The attack also depends on the presence of writable directories and the ability to trigger the deployment scanner after file placement.[/subscribe_to_unlock_form]
EXECUTIVE SUMMARY:
CVE-2026-20262 with a CVSS score of 6.5 is a critical arbitrary file write vulnerability affecting Cisco Catalyst SD‑WAN Manager (formerly SD‑WAN vManage) across all versions and deployment types. The flaw resides in the web UI file‑upload function, where user‑supplied input is not properly validated, allowing an authenticated attacker with at least write privileges to send a crafted HTTP request to the vulnerable API endpoint and specify a path‑traversal payload. By exploiting this vector, the attacker can create or overwrite any file on the underlying operating system, such as deploying a malicious WAR file into the WildFly deployment directory, which can later be executed to gain root‑level code execution. Business impact includes potential full system compromise, loss of confidentiality, integrity, and availability of the SD‑WAN management plane, and the ability for the adversary to pivot to other network components. Exploitation requires valid credentials and network access to the manager's web interface; systems exposed to the internet with open ports are especially at risk. The attack also depends on the presence of writable directories and the ability to trigger the deployment scanner after file placement.[emaillocker id="1283"]
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The following reports contain further technical details:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-arbfw-c2rZvQ