CVE-2026-20122 MEDIUM

CVE-2026-20122: Cisco Catalyst SD-WAN Manager Arbitrary File Overwrite Vulnerability

Vendor Cisco
Product Cisco Catalyst SD-WAN Manager
Weakness CWE-648
KEV Status Known Exploited
Published February 25, 2026
Last update April 21, 2026

CVSS base score

5.4/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality Low
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

What the vulnerability does

01Description

A vulnerability in the API of Cisco Catalyst SD-WAN Manager could allow an authenticated, remote attacker to overwrite arbitrary files on the local file system. To exploit this vulnerability, the attacker must have valid read-only credentials with API access on the affected system. This vulnerability is 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.

CISA mandated remediation

02CISA Required Action

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.

Key dates

03Disclosure timeline

February 25, 2026 CVE published
April 21, 2026 Record updated

External resources

04References