Cisco Catalyst SD-WAN Controller and Manager
CVE-2026-20127
Cisco Catalyst SD-WAN Controller, formerly SD-WAN vSmart, and Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, contain an authentication bypass vulnerability could allow an unauthenticated, remote attacker to bypass authentication and obtain administrative privileges on an affected system. This vulnerability exists because the peering authentication mechanism in an affected system is not working properly. An attacker could exploit this vulnerability by sending crafted requests to an affected system. A successful exploit could allow the attacker to log in to an affected Cisco Catalyst SD-WAN Controller as an internal, high-privileged, non-root user account. Using this account, the attacker could access NETCONF, which would then allow the attacker to manipulate network configuration for the SD-WAN fabric.
What this means for your business
- It affects Cisco Catalyst SD-WAN Controller and Manager. It matters if your company, or a supplier that handles your data, runs it.
- Attackers are already using it. CISA added it to its list of flaws used in real attacks on 25 February 2026.
- FIRST's prediction model gives it a 88% chance of attack attempts being seen in the next 30 days, ranking above 99% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Cisco Catalyst SD-WAN Controller and Manager.
- 2If you do, follow CISA's required action below. No patch reference has been published yet.
- 3Treat it as urgent. US federal agencies must fix it by 27 February 2026. That deadline does not apply to private companies, but it shows how seriously CISA takes it.
- 4Because attackers have used it, check the affected systems for signs of a break-in, not only for the update.
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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.
CISA’s wording, unedited. The notes it mentions are in CISA’s catalogue entry.
Scoring
- CVSS
- Not yet scored
Dates
- Published
- 2026-02-25
- Added to KEV
- 2026-02-25
- Remediation due
- 2026-02-27
- Sources
- CISA KEV