CVE-2026-20245

Cisco Catalyst SD-WAN Manager Improper Encoding or Escaping of Output Vulnerability

Actively exploited (CISA KEV) High 7.8 CVSS 3.1

Description

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.

Description as published by the source, in English.

Key facts

Published: 2026-06-04
Last modified: 2026-07-23
Assigned by: psirt@cisco.com
CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Scored by: psirt@cisco.com
Probability of exploitation: 25.3 % higher than 98 % of all known vulnerabilities
EPSS, next 30 days, model v2026.06.15
Fix available: Not registered in the sources

Actively exploited

CISA added this vulnerability to the Known Exploited Vulnerabilities catalogue on 2026-06-09, with a remediation deadline of 2026-06-23 for US federal agencies.

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.

Affected products

Vendor	Product	Versions	Status
Cisco	Catalyst Sd-wan Manager	< 20.9.9.1	Affected
Cisco	Catalyst Sd-wan Manager	20.12.7	Affected
Cisco	Catalyst Sd-wan Manager	≥ 20.10, < 20.12.5.4	Affected
Cisco	Catalyst Sd-wan Manager	≥ 20.12.6, < 20.12.6.2	Affected
Cisco	Catalyst Sd-wan Manager	≥ 20.13, < 20.15.4.4	Affected
Cisco	Catalyst Sd-wan Manager	≥ 20.15.5, < 20.15.5.2	Affected
Cisco	Catalyst Sd-wan Manager	≥ 20.16, < 20.18.2.2	Affected
Cisco	Catalyst Sd-wan Manager	≥ 26.1, < 26.1.1.1	Affected
Cisco	Sd-wan Vsmart Controller	< 20.9.9.1	Affected
Cisco	Sd-wan Vsmart Controller	20.12.7	Affected
Cisco	Sd-wan Vsmart Controller	≥ 20.10, < 20.12.5.4	Affected
Cisco	Sd-wan Vsmart Controller	≥ 20.12.6, < 20.12.6.2	Affected
Cisco	Sd-wan Vsmart Controller	≥ 20.13, < 20.15.4.4	Affected
Cisco	Sd-wan Vsmart Controller	≥ 20.15.5, < 20.15.5.2	Affected
Cisco	Sd-wan Vsmart Controller	≥ 20.16, < 20.18.2.2	Affected
Cisco	Sd-wan Vsmart Controller	≥ 26.1, < 26.1.1.1	Affected

Weakness type

CWE-116: Improper Encoding or Escaping of Output
The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not p…

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sd… Vendor Advisory
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sd… Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20245 US Government Resource

Related at Berigo

Articles

Mandiant: Cisco SD-WAN Manager zero-day exploited for months Mentions this CVE 2026-06-24
Mandiant describes how an actor exploited CVE-2026-20245 in Cisco Catalyst SD-WAN Manager from late 2025 to January 2026 and gained root access.
Approved partners get access to a model that finds unknown vulnerabilities Same product 2026-08-12
OpenAI is expanding Daybreak with two access levels and releasing GPT-5.6-Cyber, a model trained for tasks such as finding zero-day vulnerabilities a…
Cisco closes top-severity holes in SD-WAN and IOS XE, and there is no way around them Same product 2026-08-06
Cisco published security updates for Catalyst SD-WAN, IOS XE and the Integrated Management Controller on 5 August 2026. Three of the SD-WAN vulnerabi…
Static account in Cisco Secure FMC actively exploited Same product 2026-07-30
On 29 July 2026 CISA added CVE-2026-20316 to its catalog of known exploited vulnerabilities. The vulnerability is a static user account in the web in…

Does this affect you?

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Sources and freshness

CVE

What it is: A reference number naming one specific vulnerability, for example CVE-2024-9474.
What it tells you: Which vulnerability we are talking about, and in which product.
What it does NOT tell you: Nothing about how serious it is, whether anyone is exploiting it, or whether it concerns you.
Why it matters: Without a shared number, vendor, authority and tooling cannot discuss the same flaw.
Used with the others: The number is the key. NVD, KEV and EPSS all describe the same CVE.

NVD CWE CISA KEV EPSS

How to read this together

No single value should be used on its own. A high CVSS score does not mean a vulnerability is being exploited, and a low one does not mean it is harmless. The four sources answer four different questions.

CVE names the specific vulnerability.
NVD adds severity and technical detail about it.
CWE describes the type of mistake behind it.
CISA KEV shows that it is already being exploited.
EPSS estimates how likely exploitation is soon.

The order that decides what is urgent

Do you actually have the product?
Is the version you run affected?
Is it listed in CISA KEV?
Does it have a high EPSS score?
Is the system reachable from the internet or from others?
How important is the system to the business?
Are there compensating controls already in place?

The first two questions are not about the vulnerability at all. They are about you, and they remove most of the list before you start.

A short example

Fix this week

CVSS 6,5 (medium)

In CISA KEV: yes
EPSS: 94 per cent
A firewall facing the internet

Can be scheduled

CVSS 9,8 (critical)

In CISA KEV: no
EPSS: 0,04 per cent
A test server with no internet access

Sorted by CVSS alone, the one on the right comes first. It is the more serious flaw in theory. But the one on the left is being used against real organisations right now, and it sits where an attacker can reach it. That is the one to fix first.

The critical one still has to be fixed. It just does not have to be fixed today.

This product uses the NVD API but is not endorsed or certified by the NVD. CVE and the CVE logo are registered trademarks of The MITRE Corporation; CVE records are used under the CVE Terms of Use. CWE is a trademark of The MITRE Corporation, used per the CWE Terms of Use. KEV data from CISA (CC0). Exploitation probability from EPSS, a FIRST.org project. Open-source package data from OSV and the GitHub Advisory Database (CC-BY 4.0).

Scores and vectors are shown as published by the sources. The ordering of results is Berigo's own editorial assessment, described on the search page, and is not NVD data. An empty result never means a system is safe.