Cisco Catalyst SD-WAN
CVE-2026-20182
Cisco Catalyst SD-WAN Controller & Manager contain an authentication bypass vulnerability that allows an unauthenticated, remote attacker to bypass authentication and obtain administrative privileges on an affected system.
What this means for your business
- It affects Cisco Catalyst SD-WAN. 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 14 May 2026.
- FIRST's prediction model gives it a 92% 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.
- 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 17 May 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 outlined 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
- 2026-05-14
- Added to KEV
- 2026-05-14
- Remediation due
- 2026-05-17
- Sources
- CISA KEV