PatchSiren cyber security CVE debrief

CVE-2026-20262 Cisco CVE debrief

CVE-2026-20262 is a vulnerability in the web UI of Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage. The vulnerability allows an authenticated, remote attacker to create a file or overwrite any file on the filesystem of an affected system. This is possible due to improper validation of user-supplied input during a file upload process. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected API endpoint of the affected system. A successful exploit could allow the attacker to create or overwrite any file on the underlying operating system, potentially leading to elevation to root. The attacker must have valid credentials with at least a lower-privileged, single-task user account.

Vendor: Cisco
Product: Cisco Catalyst SD-WAN Manager
CVSS: MEDIUM 6.5
CISA KEV: Listed
Original CVE published: 2026-06-15
Original CVE updated: 2026-06-15
Advisory published: 2026-06-15
Advisory updated: 2026-06-15

Who should care

Administrators and users of Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, should be aware of this vulnerability and take necessary actions to mitigate it.

Technical summary

The vulnerability exists in the web UI of Cisco Catalyst SD-WAN Manager due to improper validation of user-supplied input during a file upload process. This allows an authenticated, remote attacker to create a file or overwrite any file on the filesystem of an affected system.

Defensive priority

MEDIUM

Recommended defensive actions

Apply patches or updates provided by Cisco to fix the vulnerability.
Restrict access to the affected API endpoints.
Monitor system logs for suspicious activity.

Evidence notes

The CVE-2026-20262 vulnerability has a CVSS score of 6.5 and a severity of MEDIUM. It was published on 2026-06-15T18:16:34.820Z and has not been modified since then.

Sources and references

Verified primary and authoritative sources

CVE-2026-20262 CVE Program record
Publisher, destination, and source semantics verified

URL: https://www.cve.org/CVERecord?id=CVE-2026-20262

CVE Program - Official CVE Program record with source-provided CVE metadata.
CVE-2026-20262 NVD vulnerability detail
Publisher, destination, and source semantics verified

URL: https://nvd.nist.gov/vuln/detail/CVE-2026-20262

NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Source reference
Unverified legacy reference

URL: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-arbfw-c2rZvQ

[email protected]

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.