CVE-2026-20245: Cisco Catalyst SD-WAN Manager Improper Encoding or Escaping of Output Vulnerability

What it is

A vulnerability in the CLI of 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 authenticated, local attacker to execute arbitrary commands as root by supplying a crafted file to the affected system. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by uploading a crafted file to the affected system. A successful exploit could allow the attacker to perform command injection attacks on an affected system and elevate their privileges as the root user. To exploit this vulnerability, the attacker must have netadmin privileges on the affected system. This would require valid credentials or exploitation of or . Cisco is not aware of successful exploitation by other methods. Cisco has observed limited cases where the exploitation of this bug resulted in a configuration change pushed to edge devices. Cisco recommends that customers upgrade to the fixed software that is documented in the that was published on May 14, 2026, and verify the configuration of the edge devices.

Exploitation evidence

First exploit evidence seen: 2026-06-06 (earliest date across the sources below).

Exploited in the wild

• CISA KEV: listed since 2026-06-09. Source

Public exploit code

GitHub proof-of-concept repositories

3 public repositories from 3 accounts, first seen 2026-06-06. Most starred: 0xBlackash/CVE-2026-20245 (4 stars), view repository.

Verify before running: public PoCs can be malicious. Read the code and only run it in an isolated lab. A PoC means exploit code is public, not that this CVE is exploited in the wild.

Sources: CISA KEV · nomi-sec/PoC-in-GitHub.

How to fix it

CISA required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. (source: CISA KEV)

Fixed versions

• cisco catalyst sd-wan manager: upgrade to 20.9.9.1 or later
• cisco catalyst sd-wan manager: upgrade to 20.12.5.4 or later (affected from 20.10)
• cisco catalyst sd-wan manager: upgrade to 20.12.6.2 or later (affected from 20.12.6)
• cisco catalyst sd-wan manager: upgrade to 20.15.4.4 or later (affected from 20.13)
• cisco catalyst sd-wan manager: upgrade to 20.15.5.2 or later (affected from 20.15.5)
• cisco catalyst sd-wan manager: upgrade to 20.18.2.2 or later (affected from 20.16)
• cisco catalyst sd-wan manager: upgrade to 26.1.1.1 or later (affected from 26.1)
• cisco sd-wan vsmart controller: upgrade to 20.9.9.1 or later
• cisco sd-wan vsmart controller: upgrade to 20.12.5.4 or later (affected from 20.10)
• cisco sd-wan vsmart controller: upgrade to 20.12.6.2 or later (affected from 20.12.6)
• cisco sd-wan vsmart controller: upgrade to 20.15.4.4 or later (affected from 20.13)
• cisco sd-wan vsmart controller: upgrade to 20.15.5.2 or later (affected from 20.15.5)
• cisco sd-wan vsmart controller: upgrade to 20.18.2.2 or later (affected from 20.16)
• cisco sd-wan vsmart controller: upgrade to 26.1.1.1 or later (affected from 26.1)

Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.

Vendor advisories and patches

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-privesc-4uxFrdzx (CISA KEV notes)
• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-rpa2-v69WY2SW (Vendor Advisory)

MITRE ATT&CK mitigations for this chain

• M1033 Limit Software Installation (for T1059) : Prevent user installation of unrequired command and scripting interpreters.
• M1045 Code Signing (for T1059) : Where possible, only permit execution of signed scripts.
• M1042 Disable or Remove Feature or Program (for T1059) : Disable or remove any unnecessary or unused shells or interpreters.
• M1038 Execution Prevention (for T1059) : Use application control where appropriate. For example, PowerShell Constrained Language mode can be used to restrict access to sensitive or otherwise dangerous language elements such as those used to execute arbitrary Windows APIs or files (e.g., `Add-Type`).
• M1049 Antivirus/Antimalware (for T1059) : Anti-virus can be used to automatically quarantine suspicious files.
• M1026 Privileged Account Management (for T1059) : When PowerShell is necessary, consider restricting PowerShell execution policy to administrators. Be aware that there are methods of bypassing the PowerShell execution policy, depending on environment configuration. PowerShell JEA (Just Enough Administration) may also be used to sandbox administration and limit what c
• M1047 Audit (for T1059) : Inventory systems for unauthorized command and scripting interpreter installations.
• M1021 Restrict Web-Based Content (for T1059) : Script blocking extensions can help prevent the execution of scripts and HTA files that may commonly be used during the exploitation process. For malicious code served up through ads, adblockers can help prevent that code from executing in the first place.
• M1040 Behavior Prevention on Endpoint (for T1059) : On Windows 10, enable Attack Surface Reduction (ASR) rules to prevent [Visual Basic](https://attack.mitre.org/techniques/T1059/005) and [JavaScript](https://attack.mitre.org/techniques/T1059/007) scripts from executing potentially malicious downloaded content .

Detection Generic guidance

• Execution: Watch for the service process spawning shells or script interpreters (cmd.exe, powershell, sh, bash, python) via EDR process-tree rules.

Response checklist Generic guidance

1. Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
2. Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
3. Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
4. Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.