KEV catalog · CISA Known Exploited Vulnerabilities
CVE-2026-20122
5.4
Details
Descriptions
KEV: 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.
NVD: 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.
Compliance SSVC + BOD 26-04
Research metadata
https://nvd.nist.gov/vuln/detail/cve-2026-20122
https://www.vulncheck.com/blog/cisco-sd-wan-manager-vulns
https://blog.talosintelligence.com/sd-wan-ongoing-exploitation/
https://www.darkreading.com/vulnerabilities-threats/fake-pocs-risks-cisco-sd-wan
https://github.com/zerozenxlabs/CVE-2026-20127---Cisco-SD-WAN-Preauth-RCE
https://www.sentinelone.com/vulnerability-database/cve-2026-20122/
https://dev.to/hookprobe/how-hookprobe-detects-cve-2026-20122-cisco-catalyst-sd-wan-manager-5b0p
Hunting hypothesis agent
Hunt Cisco SD-WAN Manager API logs for POST requests to /dataservice/smartLicensing/uploadAck with path traversal sequences (../../) in filenames from read-only accounts, indicating arbitrary file overwrite to gain vmanage admin privileges.
Research details
Tia coverage
When Tia's reporting first covered this CVE and whether a report claimed exploitation before the KEV listing. Lead-time deltas are measured from the exploitation report only — plain coverage is not exploitation intel. See the story links under Mentioned in for coverage detail.
Mentioned in
cisco-sd-wan-zero-day-cve-2026-20182-6th-exploited-flaw-in-2026
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