CVE-2025-20287 Overview
CVE-2025-20287 is an arbitrary file upload vulnerability in the web-based management interface of Cisco Evolved Programmable Network Manager (EPNM). An authenticated remote attacker with valid Config Manager credentials can upload arbitrary files to an affected device by sending a crafted request to a specific API endpoint. The flaw stems from improper validation of uploaded files and is classified under [CWE-434] Unrestricted Upload of File with Dangerous Type. Cisco published a security advisory tracking this issue under advisory identifier cisco-sa-epni-arb-file-upload-jjdM2P83.
Critical Impact
Successful exploitation allows an authenticated attacker to write arbitrary files to the EPNM server, enabling potential code execution, persistence, and full compromise of confidentiality, integrity, and availability of the network management platform.
Affected Products
- Cisco Evolved Programmable Network Manager (EPNM)
- Deployments exposing the web-based management interface to network-reachable users
- Instances accessible to accounts holding the Config Manager role
Discovery Timeline
- 2025-09-03 - CVE-2025-20287 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-20287
Vulnerability Analysis
The vulnerability resides in a file upload handler exposed through the EPNM web-based management interface. The API endpoint does not properly validate the content, type, or destination of files submitted by authenticated users. An attacker with Config Manager credentials can submit a crafted upload request that places attacker-controlled content on the server file system.
Because EPNM is a centralized network management platform, an attacker who plants a malicious file may pivot to executing code within the application context. This can expose credentials, device configurations, and topology data used to manage carrier and enterprise networks. The advisory rates the impact as high across confidentiality, integrity, and availability.
Root Cause
The root cause is improper server-side validation of uploaded files, mapped to [CWE-434]. The affected endpoint accepts files without enforcing safe file types, safe destination paths, or restrictions on filename and extension. This allows an authenticated user to place executable or configuration-altering content in locations reachable by application services.
Attack Vector
Exploitation requires network access to the EPNM web interface and valid Config Manager credentials. The attacker sends a crafted HTTP request to the vulnerable API endpoint containing the malicious file payload. No user interaction is required. Because the required privilege level is not administrative, compromised or over-provisioned operator accounts significantly widen the exposure. See the Cisco Security Advisory for endpoint-specific details.
Detection Methods for CVE-2025-20287
Indicators of Compromise
- Unexpected files appearing in EPNM application directories, temporary upload paths, or web-accessible locations
- Web server or application logs recording POST or PUT requests from Config Manager accounts to the file upload API endpoint identified in the Cisco advisory
- New or modified server-side scripts, JSPs, or archives on the EPNM host following authenticated sessions
- Outbound network connections from the EPNM host to unfamiliar external addresses after a suspicious upload event
Detection Strategies
- Review EPNM audit and access logs for file upload requests made by Config Manager role accounts and correlate with expected administrative workflows
- Alert on file writes to EPNM installation directories that originate from the web application process
- Baseline legitimate upload activity per user, then flag statistical anomalies in volume, file size, or extension
Monitoring Recommendations
- Forward EPNM application, web server, and operating system logs to a centralized SIEM for retention and correlation
- Monitor authentication events for Config Manager accounts, including logins from unusual source addresses or outside business hours
- Enable file integrity monitoring on EPNM web content roots and configuration directories
How to Mitigate CVE-2025-20287
Immediate Actions Required
- Apply the fixed EPNM release identified in the Cisco Security Advisory as soon as change windows allow
- Audit accounts holding the Config Manager role and remove the privilege from users who do not require it
- Rotate credentials for privileged EPNM accounts and enforce strong, unique passwords with multi-factor authentication where supported
- Restrict network access to the EPNM web management interface to trusted administrative networks only
Patch Information
Cisco has released fixed software for EPNM. Refer to the vendor advisory cisco-sa-epni-arb-file-upload-jjdM2P83 for the specific fixed version applicable to your deployment. No official workaround is documented; upgrading to the fixed release is the recommended remediation path.
Workarounds
- Limit exposure of the EPNM web interface using firewall access control lists or a management VPN until patching is complete
- Reduce the number of Config Manager accounts and require just-in-time elevation for administrative tasks
- Enable detailed logging on the EPNM host and forward events to a monitored log platform to shorten detection time if exploitation is attempted
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
