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MediumCISA KEVExploited in the wildPublic exploit

Arbitrary File Write in Cisco Catalyst SD-WAN Manager Web UI

IdentifiersCVE-2026-20262CWE-22· Improper Limitation of a Pathname…

CVE-2026-20262 is an authenticated remote arbitrary file write vulnerability in the web UI of Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage. The flaw is caused by improper validation of user-supplied input during a file upload process in an affected API endpoint, with path traversal characteristics that allow writes outside intended directories. By sending a crafted HTTP request, an attacker with valid credentials can create a new file or overwrite any file on the underlying operating system. Cisco states that the written file can subsequently be leveraged to escalate privileges to root. The issue affects multiple versions across all deployment types of Catalyst SD-WAN Manager and has been reported as actively exploited in the wild.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows arbitrary file creation or overwrite on the underlying operating system with the privileges of the vulnerable application. This creates a direct path to integrity compromise of the management plane and can be used to deploy malicious artifacts such as JSP/WAR payloads, alter application or system files, establish persistence, and subsequently escalate privileges to root. Because the affected product is the centralized SD-WAN management controller, compromise can have outsized downstream impact on managed infrastructure. Cisco and CISA both indicate the vulnerability has been actively exploited.

Mitigation

If you can’t patch tonight, do this now.

No workaround is identified in the provided content. If immediate patching is not possible, reduce exposure of the management interface by removing unnecessary internet access, restricting access through VPNs, jump hosts, or dedicated management segments, firewalling administrative endpoints, and limiting write-capable accounts to only those strictly required. Monitor for suspicious API activity, unauthorized file operations, unusual login locations, uploads of .war or index.jsp files, and subsequent access to newly deployed web applications. If compromise is suspected, collect diagnostics and perform incident response triage in accordance with Cisco and CISA guidance.

Remediation

Patch, then assume compromise.

Upgrade Cisco Catalyst SD-WAN Manager to a fixed release provided by Cisco. The content identifies fixed versions including 20.9.9.2, 20.12.7.2, 20.15.4.5, 20.15.5.3, 20.18.3.1, and 26.1.1.2, depending on the deployed release train. Cisco strongly recommends immediate patching and review of relevant logs for indicators of compromise, including /var/log/nms/vmanage-server.log, vmanage-appserver logs, and serviceproxy-access logs for suspicious file uploads, unexpected WAR deployment activity, and follow-on HTTP requests to deployed malicious content.
PUBLIC EXPLOITS

Exploits

1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).

VALID 1 / 2 TOTALView more in app
CVE-2026-20262-Cisco-Catalyst-SD-WAN-Manager-Arbitrary-File-Write-MaturityPoCVerified exploit

This repository contains a standalone Python proof-of-concept exploit for CVE-2026-20262 affecting Cisco Catalyst SD-WAN Manager (vManage), plus a small Bash verification script and supporting documentation. The main exploit file, CVE-2026-20262.py, authenticates to the target web interface via /j_security_check, extracts a CSRF token/session state, and then abuses the AnyConnect profile upload endpoint /dataservice/settings/sdra/anyconnect/profile by placing a path traversal sequence in the multipart filename field. Its core capability is authenticated arbitrary file write on the underlying system. The exploit is operational rather than framework-based: it accepts a target URL, username, password, local file path, and attacker-chosen remote path, then uploads the local file contents to that remote location. The script also includes an optional verification step using /dataservice/file/read?path=... to test whether the file is accessible after upload. The repository documentation describes likely abuse paths such as dropping a malicious WAR into /var/lib/wildfly/standalone/deployments/ for probable server-side code execution, overwriting nginx configuration under /etc/nginx/conf.d/, or writing scripts into privileged directories. Additional files include README.md and NOTAS with vulnerability context, impact, and IOC guidance, an 'Ejecución Básica' usage note with example commands, and 'Script de Verificación Rápida', a Bash helper that queries /dataservice/version to identify potentially vulnerable versions. Overall, this is a real exploit repository centered on authenticated web-based path traversal leading to arbitrary file write, with clear post-exploitation potential but no embedded reverse shell or automated second-stage payload.

fevar54Disclosed Jun 17, 2026pythonbashwebnetwork
EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
Cisco SystemsCatalyst SD-WAN Managerapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

ACTIVITY FEED

Recent activity

133 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

the hacker newsNews
Jun 24, 2026
Cisco Unified CM Flaw Exploited After PoC Reveals File-Write Path to Root

A medium-severity security flaw affecting Cisco Catalyst SD-WAN Manager that is reported as being actively exploited in the wild.

Read more
xakepNews
Jun 19, 2026
Cisco патчит уязвимость нулевого дня в SD-WAN - Хакер

Уязвимость в Cisco Catalyst SD-WAN Manager, связанная с некорректной проверкой пользовательских данных при загрузке файлов, позволяла аутентифицированному пользователю с правами записи создать или перезаписать произвольный файл через уязвимый API, что затем могло привести к повышению привилегий до root и полному захвату системы.

Read more
malware newsNews
Jun 16, 2026
Cisco security advisory (AV26-602) - Malware News - Malware Analysis, News and Indicators

An arbitrary file write vulnerability affecting Cisco Catalyst SD-WAN Manager across multiple versions and all deployment types. It is significant because Cisco is aware of exploitation and CISA added it to the KEV catalog.

Read more
ca ccsNews
Jun 16, 2026
Cisco security advisory (AV26-602) - Canadian Centre for Cyber Security

An arbitrary file write vulnerability affecting Cisco Catalyst SD-WAN Manager across multiple versions and all deployment types. It is significant because Cisco states it is aware of exploitation, and CISA added it to the KEV catalog.

Read more
What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware2

Malware families riding this exploit, with evidence and IOCs.

Detection signatures1

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity111

Community discussion across Reddit, Mastodon, and other social sources.