CVE Intelligence
CISA KEV Critical Authentication

CVE-2026-20182 — Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability

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.

Published May 14, 2026 · Updated Oct 13, 2026 · Sources: CISA Known Exploited Vulnerabilities, NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: cisco

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

How the score was calculated
  • Confirmed exploitation (CISA KEV)+35
  • Public exploit/PoC (metasploit, github)+18
  • EPSS 91.8% (30-day exploitation probability)+15
  • Technical severity (critical)+10
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Confirmed
CISA KEV, listed May 14, 2026
EPSS FIRST
91.82%
ahead of 100% of scored CVEs · Oct 14, 2026
Affects
Cisco
Catalyst Sd-wan Manager and 3 more
CVSS base
10.0
Critical · 3 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
Active
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

CISA required action CISA

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.

US federal deadline: May 17, 2026 — passed 151 day(s) ago

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Cisco Catalyst Sd-wan Manager, Cisco Cisco Catalyst SD-WAN Controller, Cisco Sd-wan Vbond Orchestrator…).
  2. Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
  3. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  4. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  5. EPSS ahead of 100% of scored CVEs: prioritize it in the patch queue.
  6. Search available logs for exploit probes matching the vulnerability class (authentication), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Cisco Catalyst Sd-wan Manager < 20.9.9.1≥ 20.10 and < 20.12.5.4≥ 20.12.6 and < 20.12.6.2≥ 20.13 and < 20.15.4.4≥ 20.15.5 and < 20.15.5.2≥ 20.16 and < 20.18.2.2≥ 26.1 and < 26.1.1.1version 20.12.7 Vulnerable NIST National Vulnerability Database
Cisco Catalyst Sd-wan Manager version 20.1.12version 19.2.1version 18.4.4version 18.4.5version 20.1.1.1version 20.1.1version 19.2.099version 18.3.6
and 26 more version 18.3.7version 19.2.0version 19.1.0version 18.4.303version 19.2.098version 18.3.6.1version 18.2.0version 17.2.8version 18.3.3.1version 18.4.0version 18.3.1version 17.2.6version 17.2.9version 17.2.5version 18.4.0.1version 18.3.3version 18.3.0version 19.2.3version 18.4.501_ESversion 20.1.2version 19.2.929version 19.2.31version 20.3.2version 19.2.4version 19.2.4.0.9version 20.1.3.1
Vulnerable CVE Program (cve.org) e CISA ADP
Cisco Cisco Catalyst SD-WAN Controller version 20.6.4version 20.9.2version 20.3.6version 20.7.2version 20.7.1version 20.5.1version 20.6.2version 19.3.0
and 121 more version 20.6.1version 17.2.4version 18.2.0version 18.4.6version 19.1.0version 19.2.4version 19.2.929version 18.3.8version 18.4.303version 18.3.7version 18.4.1version 19.2.097version 19.2.0version 19.2.099version 18.3.6version 20.4.2version 19.0.0version 20.9.1version 20.3.5version 20.3.1version 18.3.5version 20.6.3version 18.4.3version 18.4.4version 18.3.3version 17.2.8version 20.8.1version 19.2.32version 19.2.2version 17.2.5version 18.4.0version 20.4.1.1version 20.1.3version 20.1.2version 17.2.10version 19.2.098version 20.1.1version 17.2.6version 19.2.1version 18.3.4version 20.4.1version 17.2.9version 19.2.31version 19.0.1aversion 18.3.0version 17.2.7version 18.4.5version 20.3.4version 20.3.3version 20.4.1.2version 20.3.2version 18.3.1version 20.1.12version 19.2.3version 20.10.1version 20.6.5version 20.3.7version 20.9.3version 20.12.6version 20.12.4version 20.15.1version 20.9.6version 20.6.8version 20.16.1version 20.9.5.3version 20.12.4.1version 20.15.2version 20.12.5version 20.9.7version 20.15.3version 20.12.5.1version 20.12.5.2version 20.15.4version 20.9.7.1version 20.6.3.2version 20.9.8version 20.15.4.1version 20.15.4.2version 20.12.5.3version 20.12.6.1version 20.9.8.2version 20.15.5version 20.12.7version 20.9.9version 20.15.5.1version 20.15.4.3version 20.15.4.5version 20.15.5.3version 20.12.7.2version 20.9.9.2version 20.14.1version 20.11.1version 20.4.2.3version 20.3.5.1version 20.3.4.3version 20.9.3.1version 20.6.4.1version 20.3.3.2version 20.6.5.2version 20.3.7.1version 20.11.1.1version 20.10.1.1version 20.6.1.2version 20.1.3.1version 20.9.2.2version 20.6.5.3version 20.3.7.2version 20.12.3.1version 20.9.5.1version 20.6.7version 20.12.3version 20.9.5version 20.13.1version 20.12.2version 20.6.6version 20.3.8version 20.12.1version 20.9.4version 20.9.2.3version 20.6.5.4version 20.6.3.3
Vulnerable CVE Program (cve.org) e CISA ADP
Cisco Sd-wan Vbond Orchestrator < 20.9.9.1≥ 20.10 and < 20.12.5.4≥ 20.12.6 and < 20.12.6.2≥ 20.13 and < 20.15.4.4≥ 20.15.5 and < 20.15.5.2≥ 20.16 and < 20.18.2.2≥ 26.1 and < 26.1.1.1version 20.12.7 Vulnerable NIST National Vulnerability Database
Cisco Sd-wan Vsmart Controller < 20.9.9.1≥ 20.10 and < 20.12.5.4≥ 20.12.6 and < 20.12.6.2≥ 20.13 and < 20.15.4.4≥ 20.15.5 and < 20.15.5.2≥ 20.16 and < 20.18.2.2≥ 26.1 and < 26.1.1.1version 20.12.7 Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
10.0 CVSS 3.1 Critical 3.9 6.0 psirt@cisco.com via NIST National Vulnerability Database
10.0 CVSS 3.1 Critical — — GitHub, Inc. via GitHub Security Advisories
10.0 CVSS 3.1 Critical — — cisco via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H (score shown at the top: psirt@cisco.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-287 · Improper Authentication

Other CVEs with this weakness →

CISA KEV details CISA

CISA lists a CVE once it has evidence of exploitation against real targets.

Listed
May 14, 2026
Federal deadline
May 17, 2026
passed 151 day(s) ago
Ransomware use
Unknown

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.

Public exploits, PoCs and detection templates

Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.

Metasploit modules

Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.

EPSS over time FIRST

Oct 12, 2026 → Oct 14, 2026 · 3 reading(s) · max 91.82%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Review authentication logs: logins without MFA, anomalous sessions and recently created accounts.
  • Hunt retroactively in logs from before May 14, 2026 (KEV listing): exploitation may have started earlier.
web/proxy/WAF logsnetwork IDS/IPSauthentication logs

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · cisco/cisco catalyst sd-wan controller, cisco/cisco catalyst sd-wan manager
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Affected products added · cisco/catalyst sd-wan manager, cisco/sd-wan vbond orchestrator, cisco/sd-wan vsmart controller
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 10.0
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Added to CISA KEV (detected)
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • Record created in this database
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • CVE published
    May 14, 2026 · cisco
  • Added to CISA KEV catalog
    May 13, 2026 · CISA

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 13, 2026 – Oct 13, 2026
  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

5 on the record

Elsewhere on this site

Cisco
every CVE for this vendor
2026-05
what else CISA listed that month
Authentication
same class
CWE-287
other pages naming this weakness

Related CVEs (same products)

  • Critical CVE-2026-76504 Cisco Catalyst SD-WAN Manager Hex Encoding Vulnerability KEV 15d
  • Medium CVE-2026-20262 Cisco Catalyst SD-WAN Manager Directory or Path Traversal Vulnerability KEV Jun 15, 2026
  • High CVE-2026-20245 Cisco Catalyst SD-WAN Manager Improper Encoding or Escaping of Output Vulnerability KEV Jun 4, 2026
  • High CVE-2026-20224 Cisco Catalyst SD-WAN Manager XML External Entity Injection Vulnerability May 14, 2026
  • Medium CVE-2026-20210 Cisco Catalyst SD-WAN Manager Privilege Escalation Vulnerability May 14, 2026
  • Medium CVE-2026-20209 Cisco Catalyst SD-WAN Manager Privilege Escalation Vulnerability May 14, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-20182 is "Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability", rated Critical. It affects Catalyst Sd-wan Manager (Cisco); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 10.0 describes technical severity. EPSS 91.82% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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