Cisco Catalyst SD-WAN Manager Arbitrary File Write Vulnerability
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Listed in CISA KEV
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Actively exploited
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Cisco Catalyst SD-WAN Manager (formerly SD-WAN vManage), specifically its web interface, is affected by this flaw. A remote attacker with valid low-privilege credentials could create or overwrite any file on the underlying system, which could later be used to gain root-level control.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original description
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 overwrite any file on the filesystem of an affected system. This vulnerability exists because the affected software does not properly validate 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. This file could later be used to elevate to root. To exploit this vulnerability, the attacker must have valid credentials with at least a lower-privileged, single-task user account.
Timeline
- Added to CISA KEV
CISA has evidence of exploitation in the wild
- CVE published
- Record last updated
- CISA remediation deadline
Due date for US federal agencies to patch
- EPSS reached 10%
FIRST estimates at least a 10% chance of exploitation in the next 30 days
Affected versions
- Cisco Cisco Catalyst SD-WAN Manager
20.1.12, 19.2.1, 18.4.4, 18.4.5, 20.1.1.1, 20.1.1, 19.3.0, 19.2.2, 19.2.099, 18.3.6, 18.3.7, 19.2.0, 18.3.8, 19.0.0, 19.1.0, 18.4.302, 18.4.303, 19.2.097, 19.2.098, 17.2.10, 18.3.6.1, 19.0.1a, 18.2.0, 18.4.3, 18.4.1, 17.2.8, 18.3.3.1, 18.4.0, 18.3.1, 17.2.6, and 346 more
References 1
sec.cloudapps.cisco.com
Questions about CVE-2026-20262
What does this mean?
An attacker with valid credentials that have at least write access can create or overwrite any file on the underlying operating system of Cisco Catalyst SD-WAN Manager. The advisory says this could later be used to elevate privileges to root.Source: sec.cloudapps.cisco.com
Am I affected, and how do I check?
The advisory says the flaw affects Cisco Catalyst SD-WAN Manager regardless of device configuration, but the checked facts do not list the affected release numbers. To check a installed release, compare it with the versions listed as affected in Cisco's advisory. Exposure also requires valid credentials with at least write access.Source: sec.cloudapps.cisco.com
What should I do about it?
The checked facts do not name a fixed release. Consult Cisco's advisory for the release that contains the fix and the affected version list.Source: sec.cloudapps.cisco.com
Is it being exploited?
Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2026-06-15, which means it has evidence of attacks. No public exploit code is tracked.Source: cisa.gov, cve.now feed data
What if there's no patch?
The checked facts do not list a workaround. Because the attack requires valid credentials with at least write access, limiting which accounts hold that level of access on the Manager is the only mitigation the facts support.Source: sec.cloudapps.cisco.com