CriticalCVE-2026-20182

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

    Published Last modified In CISA KEV since Sources: SingCERT, CVE.org, pwn.watch, Cisco PSIRT, EUVD

    What is affected, what to do

    An unauthenticated attacker can bypass authentication and gain administrative privileges on affected Cisco Catalyst SD-WAN systems due to a vulnerability in the peering authentication mechanism. This vulnerability allows attackers to send crafted requests, enabling them to manipulate the network configuration. The vulnerability is actively exploited, as evidenced by its inclusion in the CISA KEV catalog. Affected products include specific versions of the Cisco Catalyst SD-WAN Manager, with patches available for versions 20.9.9.2 and higher, and 26.1.1.2 and higher. Immediate patching of affected systems is imperative to mitigate the risk.

    The vulnerability is being actively exploited; treat it as a priority. Update catalyst_sd-wan_manager to version 20.18.2.2, sd-wan_vbond_orchestrator to version 20.12.5.4, sd-wan_vsmart_controller to version 20.12.5.4. Immediate actions, mitigation and detection rules are in the runbook below.

    Affected
    • Cisco Catalyst SD-WAN Controller eq 20.6.4..20.6.4
    • Cisco Catalyst SD-WAN Controller eq 20.9.2..20.9.2
    • Cisco Catalyst SD-WAN Controller eq 20.3.6..20.3.6
    • Cisco Catalyst SD-WAN Controller eq 20.7.2..20.7.2
    • Cisco Catalyst SD-WAN Controller eq 20.7.1..20.7.1
    • Cisco Catalyst SD-WAN Controller eq 20.5.1..20.5.1
    • Cisco Catalyst SD-WAN Controller eq 20.6.2..20.6.2
    • Cisco Catalyst SD-WAN Controller eq 19.3.0..19.3.0
    • Cisco Catalyst SD-WAN Controller eq 20.6.1..20.6.1
    • Cisco Catalyst SD-WAN Controller eq 17.2.4..17.2.4
    • Cisco Catalyst SD-WAN Controller eq 18.2.0..18.2.0
    • Cisco Catalyst SD-WAN Controller eq 18.4.6..18.4.6
    • Cisco Catalyst SD-WAN Controller eq 19.1.0..19.1.0
    • Cisco Catalyst SD-WAN Controller eq 19.2.4..19.2.4
    • Cisco Catalyst SD-WAN Controller eq 19.2.929..19.2.929
    • Cisco Catalyst SD-WAN Controller eq 18.3.8..18.3.8
    • Cisco Catalyst SD-WAN Controller eq 18.4.303..18.4.303
    • Cisco Catalyst SD-WAN Controller eq 18.3.7..18.3.7
    • Cisco Catalyst SD-WAN Controller eq 18.4.1..18.4.1
    • Cisco Catalyst SD-WAN Controller eq 19.2.097..19.2.097
    • Cisco Catalyst SD-WAN Controller eq 19.2.0..19.2.0
    • Cisco Catalyst SD-WAN Controller eq 19.2.099..19.2.099
    • Cisco Catalyst SD-WAN Controller eq 18.3.6..18.3.6
    • Cisco Catalyst SD-WAN Controller eq 20.4.2..20.4.2
    • Cisco Catalyst SD-WAN Controller eq 19.0.0..19.0.0
    • Cisco Catalyst SD-WAN Controller eq 20.9.1..20.9.1
    • Cisco Catalyst SD-WAN Controller eq 20.3.5..20.3.5
    • Cisco Catalyst SD-WAN Controller eq 20.3.1..20.3.1
    • Cisco Catalyst SD-WAN Controller eq 18.3.5..18.3.5
    • Cisco Catalyst SD-WAN Controller eq 20.6.3..20.6.3
    • Cisco Catalyst SD-WAN Controller eq 18.4.3..18.4.3
    • Cisco Catalyst SD-WAN Controller eq 18.4.4..18.4.4
    • Cisco Catalyst SD-WAN Controller eq 18.3.3..18.3.3
    • Cisco Catalyst SD-WAN Controller eq 17.2.8..17.2.8
    • Cisco Catalyst SD-WAN Controller eq 20.8.1..20.8.1
    • Cisco Catalyst SD-WAN Controller eq 19.2.32..19.2.32
    • Cisco Catalyst SD-WAN Controller eq 19.2.2..19.2.2
    • Cisco Catalyst SD-WAN Controller eq 17.2.5..17.2.5
    • Cisco Catalyst SD-WAN Controller eq 18.4.0..18.4.0
    • Cisco Catalyst SD-WAN Controller eq 20.4.1.1..20.4.1.1
    • Cisco Catalyst SD-WAN Controller eq 20.1.3..20.1.3
    • Cisco Catalyst SD-WAN Controller eq 20.1.2..20.1.2
    • Cisco Catalyst SD-WAN Controller eq 17.2.10..17.2.10
    • Cisco Catalyst SD-WAN Controller eq 19.2.098..19.2.098
    • Cisco Catalyst SD-WAN Controller eq 20.1.1..20.1.1
    • Cisco Catalyst SD-WAN Controller eq 17.2.6..17.2.6
    • Cisco Catalyst SD-WAN Controller eq 19.2.1..19.2.1
    • Cisco Catalyst SD-WAN Controller eq 18.3.4..18.3.4
    • Cisco Catalyst SD-WAN Controller eq 20.4.1..20.4.1
    • Cisco Catalyst SD-WAN Controller eq 17.2.9..17.2.9
    • Cisco Catalyst SD-WAN Controller eq 19.2.31..19.2.31
    • Cisco Catalyst SD-WAN Controller eq 19.0.1a..19.0.1a
    • Cisco Catalyst SD-WAN Controller eq 18.3.0..18.3.0
    • Cisco Catalyst SD-WAN Controller eq 17.2.7..17.2.7
    • Cisco Catalyst SD-WAN Controller eq 18.4.5..18.4.5
    • Cisco Catalyst SD-WAN Controller eq 20.3.4..20.3.4
    • Cisco Catalyst SD-WAN Controller eq 20.3.3..20.3.3
    • Cisco Catalyst SD-WAN Controller eq 20.4.1.2..20.4.1.2
    • Cisco Catalyst SD-WAN Controller eq 20.3.2..20.3.2
    • Cisco Catalyst SD-WAN Controller eq 18.3.1..18.3.1
    • Cisco Catalyst SD-WAN Controller eq 20.1.12..20.1.12
    • Cisco Catalyst SD-WAN Controller eq 19.2.3..19.2.3
    • Cisco Catalyst SD-WAN Controller eq 20.10.1..20.10.1
    • Cisco Catalyst SD-WAN Controller eq 20.6.5..20.6.5
    • Cisco Catalyst SD-WAN Controller eq 20.3.7..20.3.7
    • Cisco Catalyst SD-WAN Controller eq 20.9.3..20.9.3
    • Cisco Catalyst SD-WAN Controller eq 20.11.1..20.11.1
    • Cisco Catalyst SD-WAN Controller eq 20.6.3.2..20.6.3.2
    • Cisco Catalyst SD-WAN Controller eq 20.4.2.3..20.4.2.3
    • Cisco Catalyst SD-WAN Controller eq 20.3.5.1..20.3.5.1
    • Cisco Catalyst SD-WAN Controller eq 20.3.4.3..20.3.4.3
    • Cisco Catalyst SD-WAN Controller eq 20.9.3.1..20.9.3.1
    • Cisco Catalyst SD-WAN Controller eq 20.6.4.1..20.6.4.1
    • Cisco Catalyst SD-WAN Controller eq 20.3.3.2..20.3.3.2
    • Cisco Catalyst SD-WAN Controller eq 20.6.5.2..20.6.5.2
    • Cisco Catalyst SD-WAN Controller eq 20.3.7.1..20.3.7.1
    • Cisco Catalyst SD-WAN Controller eq 20.11.1.1..20.11.1.1
    • Cisco Catalyst SD-WAN Controller eq 20.10.1.1..20.10.1.1
    • Cisco Catalyst SD-WAN Controller eq 20.6.1.2..20.6.1.2
    • Cisco Catalyst SD-WAN Controller eq 20.1.3.1..20.1.3.1
    • Cisco Catalyst SD-WAN Controller eq 20.9.2.2..20.9.2.2
    • Cisco Catalyst SD-WAN Controller eq 20.6.5.3..20.6.5.3
    • Cisco Catalyst SD-WAN Controller eq 20.6.3.3..20.6.3.3
    • Cisco Catalyst SD-WAN Controller eq 20.3.7.2..20.3.7.2
    • Cisco Catalyst SD-WAN Controller eq 20.6.5.4..20.6.5.4
    • Cisco Catalyst SD-WAN Controller eq 20.9.2.3..20.9.2.3
    • Cisco Catalyst SD-WAN Controller eq 20.9.4..20.9.4
    • Cisco Catalyst SD-WAN Controller eq 20.12.1..20.12.1
    • Cisco Catalyst SD-WAN Controller eq 20.3.8..20.3.8
    • Cisco Catalyst SD-WAN Controller eq 20.6.6..20.6.6
    • Cisco Catalyst SD-WAN Controller eq 20.12.2..20.12.2
    • Cisco Catalyst SD-WAN Controller eq 20.13.1..20.13.1
    • Cisco Catalyst SD-WAN Controller eq 20.9.5..20.9.5
    • Cisco Catalyst SD-WAN Controller eq 20.12.3..20.12.3
    • Cisco Catalyst SD-WAN Controller eq 20.6.7..20.6.7
    • Cisco Catalyst SD-WAN Controller eq 20.9.5.1..20.9.5.1
    • Cisco Catalyst SD-WAN Controller eq 20.14.1..20.14.1
    • Cisco Catalyst SD-WAN Controller eq 20.12.3.1..20.12.3.1
    • Cisco Catalyst SD-WAN Controller eq 20.12.4..20.12.4
    • Cisco Catalyst SD-WAN Controller eq 20.15.1..20.15.1
    • Cisco Catalyst SD-WAN Controller eq 20.9.6..20.9.6
    • Cisco Catalyst SD-WAN Controller eq 20.6.8..20.6.8
    • Cisco Catalyst SD-WAN Controller eq 20.16.1..20.16.1
    • Cisco Catalyst SD-WAN Controller eq 20.9.5.3..20.9.5.3
    • Cisco Catalyst SD-WAN Controller eq 20.12.4.1..20.12.4.1
    • Cisco Catalyst SD-WAN Controller eq 20.15.2..20.15.2
    • Cisco Catalyst SD-WAN Controller eq 20.12.5..20.12.5
    • Cisco Catalyst SD-WAN Controller eq 20.9.7..20.9.7
    • Cisco Catalyst SD-WAN Controller eq 20.15.3..20.15.3
    • Cisco Catalyst SD-WAN Controller eq 20.12.5.1..20.12.5.1
    • Cisco Catalyst SD-WAN Controller eq 20.12.5.2..20.12.5.2
    • Cisco Catalyst SD-WAN Controller eq 20.15.4..20.15.4
    • Cisco Catalyst SD-WAN Controller eq 20.9.7.1..20.9.7.1
    • Cisco Catalyst SD-WAN Controller eq 20.12.6..20.12.6
    • Cisco Catalyst SD-WAN Controller eq 20.9.8..20.9.8
    • Cisco Catalyst SD-WAN Controller eq 20.15.4.1..20.15.4.1
    • Cisco Catalyst SD-WAN Controller eq 20.15.4.2..20.15.4.2
    • Cisco Catalyst SD-WAN Controller eq 20.12.5.3..20.12.5.3
    • Cisco Catalyst SD-WAN Controller eq 20.12.6.1..20.12.6.1
    • Cisco Catalyst SD-WAN Controller eq 20.9.8.2..20.9.8.2
    • Cisco Catalyst SD-WAN Controller eq 20.15.5..20.15.5
    • Cisco Catalyst SD-WAN Controller eq 20.12.7..20.12.7
    • Cisco Catalyst SD-WAN Controller eq 20.9.9..20.9.9
    • Cisco Catalyst SD-WAN Controller eq 20.15.5.1..20.15.5.1
    • Cisco Catalyst SD-WAN Controller eq 20.15.4.3..20.15.4.3
    • Cisco Catalyst SD-WAN Controller eq 20.15.4.5..20.15.4.5
    • Cisco Catalyst SD-WAN Controller eq 20.15.5.3..20.15.5.3
    • Cisco Catalyst SD-WAN Controller eq 20.12.7.2..20.12.7.2
    • Cisco Catalyst SD-WAN Controller eq 20.9.9.2..20.9.9.2
    • Cisco Catalyst SD-WAN Manager eq 20.1.12..20.1.12
    • Cisco Catalyst SD-WAN Manager eq 19.2.1..19.2.1
    • Cisco Catalyst SD-WAN Manager eq 18.4.4..18.4.4
    • Cisco Catalyst SD-WAN Manager eq 18.4.5..18.4.5
    • Cisco Catalyst SD-WAN Manager eq 20.1.1.1..20.1.1.1
    • Cisco Catalyst SD-WAN Manager eq 20.1.1..20.1.1
    • Cisco Catalyst SD-WAN Manager eq 19.2.099..19.2.099
    • Cisco Catalyst SD-WAN Manager eq 18.3.6..18.3.6
    • Cisco Catalyst SD-WAN Manager eq 18.3.7..18.3.7
    • Cisco Catalyst SD-WAN Manager eq 19.2.0..19.2.0
    • Cisco Catalyst SD-WAN Manager eq 19.1.0..19.1.0
    • Cisco Catalyst SD-WAN Manager eq 18.4.303..18.4.303
    • Cisco Catalyst SD-WAN Manager eq 19.2.098..19.2.098
    • Cisco Catalyst SD-WAN Manager eq 18.3.6.1..18.3.6.1
    • Cisco Catalyst SD-WAN Manager eq 18.2.0..18.2.0
    • Cisco Catalyst SD-WAN Manager eq 17.2.8..17.2.8
    • Cisco Catalyst SD-WAN Manager eq 18.3.3.1..18.3.3.1
    • Cisco Catalyst SD-WAN Manager eq 18.4.0..18.4.0
    • Cisco Catalyst SD-WAN Manager eq 18.3.1..18.3.1
    • Cisco Catalyst SD-WAN Manager eq 17.2.6..17.2.6
    • Cisco Catalyst SD-WAN Manager eq 17.2.9..17.2.9
    • Cisco Catalyst SD-WAN Manager eq 17.2.5..17.2.5
    • Cisco Catalyst SD-WAN Manager eq 18.4.0.1..18.4.0.1
    • Cisco Catalyst SD-WAN Manager eq 18.3.3..18.3.3
    • Cisco Catalyst SD-WAN Manager eq 18.3.0..18.3.0
    • Cisco Catalyst SD-WAN Manager eq 19.2.3..19.2.3
    • Cisco Catalyst SD-WAN Manager eq 18.4.501_ES..18.4.501_ES
    • Cisco Catalyst SD-WAN Manager eq 20.1.2..20.1.2
    • Cisco Catalyst SD-WAN Manager eq 19.2.929..19.2.929
    • Cisco Catalyst SD-WAN Manager eq 19.2.31..19.2.31
    • Cisco Catalyst SD-WAN Manager eq 20.3.2..20.3.2
    • Cisco Catalyst SD-WAN Manager eq 19.2.4..19.2.4
    • Cisco Catalyst SD-WAN Manager eq 19.2.4.0.9..19.2.4.0.9
    • Cisco Catalyst SD-WAN Manager eq 20.1.3.1..20.1.3.1

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    10.0

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: NVD, CVSS v3

    10.0

    CVSS v3

    Severity Critical on the scale from 0 to 10.

    Source: SingCERT, CVE.org, pwn.watch, Cisco PSIRT, EUVD

    91.8 %

    EPSS score

    High — model estimates ≥ 50% chance of real-world exploitation within 30 days.

    Source: FIRST EPSS, percentile 99.81

    Show all metrics
    Severity
    Critical
    Priority (0–325)

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

    Read in glossary
    247.13 Methodology
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

    Read in glossary
    actively exploitedSource: VulnCheck KEV (opens in a new tab), CSA/SingCERT How we classify
    XIEM Effective CVSS

    XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.

    Read in glossary
    10.0 Methodology
    CVSS v3

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    10.0
    EPSS score

    The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.

    Read in glossary
    91.8 %
    High — model estimates ≥ 50% chance of real-world exploitation within 30 days.
    EPSS percentile

    The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.

    Read in glossary
    99.81
    Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    Actively exploited
    Published
    In CISA KEV since

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    CISA assessment (SSVC)
    Exploitation: active · automatable · Technical impact: total
    Source: CISA Vulnrichment, as of 14 May 2026
    CWE

    CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.

    Read in glossary
    CWE-287

    Response and mitigation

    Why act now?

    Prioritisation rationale

    This flaw is network-reachable without authentication, needs no user interaction and has a changed scope. Successful exploitation hands the attacker the control plane of the entire SD-WAN fabric, with NETCONF access to rewrite routing, segmentation and VPN policy across every site. It sits among the CVEs most likely to be exploited, and SD-WAN controllers have been an active target since the February 2026 disclosure, mainly at service providers, public-sector bodies and operators of distributed site networks. No ransomware use is flagged, but that does not lower urgency. Treat any Internet-reachable controller component as a 24-hour emergency patch that includes a compromise assessment.

    1. Runbook step 1

      Immediate response (0-24 h)

      • Inventory every SD-WAN control component now: Cover all Catalyst SD-WAN Controller (vSmart), Manager (vManage) and Validator (vBond) instances, including Cisco-hosted cloud tenants. Match their versions against the Cisco advisory. The context lists Manager 18.3.6, 18.4.4, 18.4.5, 19.2.1, 19.2.099, 20.1.1, 20.1.1.1 and 20.1.12 among the affected releases.
      • Upgrade to the fixed release: A patch is available from the vendor. Look up the exact target version in the vendor advisory and roll out in this order: Validator → Controller → Manager. Note: being patched for the February 2026 SD-WAN advisory does not cover this new control-connection handshake flaw.
      • Audit control connections: Run show control connections and show control connections-history on every Controller and Validator. Treat any peer with an unknown system-ip, serial number, public IP or unexpected peer type as an indicator of compromise, and isolate it.
      • Restrict exposure: Temporarily restrict Internet access to the control-plane ports to known edge public IPs. Defaults are DTLS UDP 12346–12446 and TLS TCP 23456–24156; verify the ports your deployment actually uses. Allow vManage HTTPS 443/8443 and NETCONF TCP 830 only from the management network.
      • If compromise is suspected: Collect request admin-tech from all controllers before remediating. Then rotate local admin, NETCONF and API credentials and certificates, and diff the running configuration against a known-good baseline. Open a Cisco TAC case and assess NIS2 incident-reporting obligations.

    2. Runbook step 2

      Mitigation layers

      • Network segmentation: Place the controllers in a dedicated management zone. Apply a perimeter allow-list of edge-router public IPs to the control-plane ports and drop everything else. Allow NETCONF (TCP 830) and SSH (TCP 22) to the controllers only from jump-host subnets.
      • Overlay peer allow-listing: Keep the WAN Edge serial allow-list in vManage tight. Mark unused or staging entries as invalid so that unknown devices cannot establish control connections.
      • IPS/firewall: On Suricata or Firepower, alert on DTLS/TLS handshakes to control-plane ports from non-inventoried source IPs. Rate-limit new sessions per source. Enable vendor Talos/Snort signatures for this CVE once they are published.
      • IAM / least privilege: Review internal high-privilege and NETCONF accounts. Enforce TACACS+/RADIUS with MFA for vManage admin access and keep local fallback accounts to a minimum.
      • Configuration integrity: Export device templates, feature templates and policies daily and diff them automatically. Alert on unexpected changes to routing, VPN or control policies.

    3. Runbook step 3

      Detection rules

      • Control-connection anomalies: Forward controller syslog to the SIEM and alert on new control-connection events from a non-inventoried system-ip or serial. Example SPL: index=sdwan "control-connection" state=up | lookup sdwan_inventory system_ip OUTPUT known | where isnull(known).
      • NETCONF access: Flag NETCONF sessions (TCP 830) to the controllers or Manager from unexpected sources, especially those using internal service accounts. Example Zeek filter: conn.log id.resp_p==830 AND id.orig_h NOT IN mgmt_subnets.
      • Login anomalies: Search controller auth logs for successful logins by internal, non-interactive accounts without a preceding normal authentication flow. Also flag logins outside maintenance windows.
      • Configuration changes: Review the vManage audit log for template or policy pushes, new users or modified control policies that lack a matching change ticket, and correlate them with ITSM.
      • Network telemetry: Use Suricata or NetFlow to spot unusual volumes of DTLS handshakes on UDP 12346–12446 from single Internet sources, which indicate scanning or exploit attempts.

    Detection rules

    No NEOSEC detection rule is available for this vulnerability yet.

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

    Read in glossary
    Actively exploited: treat the vulnerability as a priority in vulnerability handling under Art. 21(2)(e) NIS2. If it is exploited in your environment, check the reporting obligation under Art. 23 (early warning within 24 hours).
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

    Read in glossary
    Since 11.09.2026, manufacturers of affected products with digital elements must report actively exploited vulnerabilities under Art. 14 CRA, with an early warning within 24 hours via ENISA's single reporting platform.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

    Read in glossary
    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    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.

    Source: CSA/SingCERT, NVD (NIST), pwn.watch, cvelistv5, CISA KEV Catalog, cisco_csaf, ENISA EUVD, CVE.org (MITRE)

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    Affected versionsFixed in
    CiscoCisco Catalyst SD-WAN Controller
    • 20.6.1
    • 17.2.5
    • 19.2.3
    • 19.1.0
    • 20.9.5.1
    • 20.4.1.1
    • 20.14.1
    • 20.1.2
    • 17.2.9
    • 20.3.3.2
    • 20.9.7.1
    • 20.3.1
    • 20.13.1
    • 20.6.5.4
    • 20.12.4.1
    • 20.15.5
    • 18.4.3
    • 20.6.6
    • 18.3.3
    • 20.15.3
    • 19.0.0
    • 20.3.8
    • 20.1.1
    • 18.4.0
    • 20.9.3.1
    • 17.2.7
    • 18.2.0
    • 20.3.7.1
    • 20.6.1.2
    • 20.6.7
    • 20.10.1.1
    • 20.8.1
    • 17.2.4
    • 20.9.1
    • 20.3.7.2
    • 20.15.5.1
    • 19.2.097
    • 20.4.2
    • 18.3.0
    • 20.11.1
    • 20.6.3
    • 20.12.5
    • 20.12.1
    • 20.3.5
    • 20.4.1
    • 20.9.8
    • 20.12.3.1
    • 20.15.1
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    Vendors and products

    Weakness classes (CWE)

    • CWE-287Improper Authentication

      Class

      When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

      Entry at MITRE CWE-287

    Public exploit references

    Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.

    Public exploit references
    CISA KEV CatalogCISA Known Exploited Vulnerability (opens in a new tab)cisa.govactively exploited
    CSA/SingCERTActive Exploitation of Critical Vulnerability in Cisco Catalyst SD-WAN (opens in a new tab)CSA/SingCERTactively exploited
    PoC-in-GitHub (nomi-sec)CVE-2026-20182 (opens in a new tab)github.comPoC (publicly reported)reported, not verified
    PoC-in-GitHub (nomi-sec)CVE-2026-20182 (opens in a new tab)github.comPoC (publicly reported)reported, not verified
    PoC-in-GitHub (nomi-sec)CVE-2026-20182 (opens in a new tab)github.comPoC (publicly reported)reported, not verified

    References & sources

    • sec.cloudapps.cisco.comcisco-sa-sdwan-rpa2-v69WY2SWeuvd, pwn-watch, Vendor advisory
    • sec.cloudapps.cisco.comCisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability</a> was disclosed in February 2026. This new advisory is for a new vulnerability in the control connection handshaking. The <a href="#IOC">Indicators of Compromiseeuvd, Not applicable
    • cisa.govknown-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20182government-resource, US government resource
    • pwn.watchpwn.watch: Cisco Catalyst SD-WAN: Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerabilitypwn-watch
    • NVD (NIST)NVD: CVE-2026-20182pwn-watch
    • cisa.govCISA Known Exploited Vulnerabilities Catalogpwn-watch

    Changes to this CVE

    Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

    1. Record modifiedCisco

      Description added or changed

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Descriptionchanged
      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.&nbsp; A vulnerability in the peering authentication in Cisco Catalyst SD-WAN Controller, formerly SD-WAN vSmart, and Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, 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.
      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.&nbsp; 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.

      Source identifier: psirt@cisco.com

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