Full Report
Cisco has released security updates for a medium-severity security flaw in Catalyst SD-WAN Manager that has come under active exploitation in the wild. The vulnerability, tracked as CVE-2026-20262, carries a CVSS score of 6.5 out of 10.0. "A vulnerability in the web UI of Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, could allow an authenticated, remote attacker to create a file or
Analysis Summary
# Vulnerability: Cisco Catalyst SD-WAN Manager File Creation Vulnerability
## CVE Details
- **CVE ID:** CVE-2026-20262
- **CVSS Score:** 6.5 (Medium)
- **CWE:** CWE-22 (Improper Limitation of a Pathname to a Restricted Directory / Path Traversal) or CWE-73 (External Control of File Name or Path) *[Note: Specific CWE depends on the underlying mechanism of the unauthorized file creation].*
## Affected Systems
- **Products:** Cisco Catalyst SD-WAN Manager (formerly Cisco SD-WAN vManage).
- **Versions:** Affected versions typically include releases prior to the patched software train. Specific software lifecycle versions (e.g., 20.6, 20.9, 20.12) should be checked against the official Cisco advisory.
- **Configurations:** Systems with the Web User Interface (Web UI) enabled and accessible.
## Vulnerability Description
A vulnerability exists in the Web UI of Cisco Catalyst SD-WAN Manager that could allow an authenticated, remote attacker to create arbitrary files on the underlying filesystem. The flaw stems from insufficient validation of user-supplied input within the management interface. While the attacker requires valid credentials to log into the Web UI, the flaw allows them to bypass intended restrictions to write data to locations that should normally be restricted.
## Exploitation
- **Status:** **Exploited in the wild.** Cisco has confirmed active exploitation of this flaw.
- **Complexity:** Low (Requires authentication, but the action itself is straightforward through the UI).
- **Attack Vector:** Network (Remote via HTTPS).
## Impact
- **Confidentiality:** None/Low (Primarily a write-action vulnerability).
- **Integrity:** High (Unauthorized file creation can disrupt system configuration or be used for persistence).
- **Availability:** Low/Medium (Potential to overwrite system files or fill disk space).
## Remediation
### Patches
Cisco has released software updates to address this vulnerability. Users are recommended to migrate to the following or later versions:
- Cisco Catalyst SD-WAN Manager Release 20.12.x
- Cisco Catalyst SD-WAN Manager Release 20.9.x
- Cisco Catalyst SD-WAN Manager Release 20.6.x
*(Exact maintenance release numbers should be verified via the Cisco Software Central portal).*
### Workarounds
- There are no known workarounds that fully address the vulnerability while maintaining Web UI functionality.
- **Immediate Mitigation:** Restrict Web UI access to trusted internal networks or VPNs using Access Control Lists (ACLs) to reduce the attack surface.
## Detection
- **Indicators of Compromise:** Monitor system logs for unusual file creation events or unexpected modifications to the filesystem, particularly those originating from the web server user.
- **Audit Logs:** Review Cisco SD-WAN Manager audit logs for suspicious activity associated with authenticated sessions or unusual API calls.
- **Detection methods:** Employ IDS/IPS signatures specifically tuned to look for path traversal sequences or unauthorized file upload/creation requests directed at the SD-WAN Manager URL.
## References
- Cisco Security Advisory: hxxps[://]sec[.]cloudapps[.]cisco[.]com/security/center/publicationListing[.]x
- Cisco Support and Downloads: hxxps[://]software[.]cisco[.]com/download/home