CVE-2026-20122
MEDIUM CISA KEV Actively ExploitedCisco Catalyst SD-WAN Manager Arbitrary File Overwrite Vulnerability
CVSS v3
5.4
MEDIUM
EPSS Score
1.1%
exploit probability
CISA KEV
Yes
known exploited
Exploitation
active
SSVC status
Description
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 expl
CISA Known Exploited Vulnerability
- Date Added
- 4/20/2026
- Patch Due Date
- 4/23/2026
- 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.
Technical Details
- CVSS v3 Vector
- 3.1
- Published
- 2/25/2026
- Last Modified
- 4/21/2026
Frequently Asked Questions
What is CVE-2026-20122?
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 expl
Is CVE-2026-20122 actively exploited?
Yes. CVE-2026-20122 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 4/23/2026.
What is the CVSS score for CVE-2026-20122?
CVE-2026-20122 has a CVSS v3 base score of 5.4 (MEDIUM severity), with vector string 3.1.
Is CVE-2026-20122 affecting your environment?
Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.