Known exploited · Cisco
CVE-2026-20122: Cisco Catalyst SD-WAN Manager Incorrect Use of Privileged APIs Vulnerability
What it is
Cisco Catalyst SD-WAN Manager contains an incorrect use of privileged APIs vulnerability due to improper file handling on the API interface of an affected system. An attacker could exploit this vulnerability by uploading a malicious file on the local file system. A successful exploit could allow the attacker to overwrite arbitrary files on the affected system and gain vmanage user privileges.
- Vendor
- Cisco
- Product
- Catalyst SD-WAN Manger
- Added to KEV
- April 20, 2026
- CISA due date
- April 23, 2026
- Ransomware use
- Unknown
What CISA requires
Please adhere to CISA’s guidelines to assess exposure and mitigate risks associated with Cisco SD-WAN devices as outlines in CISA’s Emergency Directive 26-03 (URL listed below in Notes) and CISA’s “Hunt & Hardening Guidance for Cisco SD-WAN Devices (URL listed below in Notes). Adhere to the applicable BOD 22-01 guidance for cloud services or discontinue use of the product if mitigations are not available.
Forensic triage
No
What to do now
- Find every instance of Catalyst SD-WAN Manger you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before April 23, 2026 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.