CVE-2025-20275 Overview
CVE-2025-20275 is an insecure deserialization vulnerability in the Cisco Unified Contact Center Express (Unified CCX) Editor. The flaw exists in how the editor processes .aef script files during the file opening operation. An attacker can craft a malicious .aef file and persuade a local user to open it, triggering arbitrary code execution in the context of that user. The issue is tracked as CWE-502: Deserialization of Untrusted Data and affects Unified CCX versions from 8.5(1) through 12.5(1) SU3.
Critical Impact
Successful exploitation allows arbitrary code execution on the host running the Unified CCX Editor with the privileges of the user who launched the application.
Affected Products
- Cisco Unified Contact Center Express 8.5(1) through 11.6(2) ES08
- Cisco Unified Contact Center Express 12.0(1) and ES01 through ES04
- Cisco Unified Contact Center Express 12.5(1) including SU1, SU2, SU3, and associated engineering specials
Discovery Timeline
- 2025-06-04 - CVE-2025-20275 published to NVD
- 2025-07-22 - Last updated in NVD database
Technical Details for CVE-2025-20275
Vulnerability Analysis
The Unified CCX Editor is a Java-based application used by contact center administrators to develop and maintain call-handling scripts. These scripts are stored as .aef files, which contain serialized Java objects representing script logic, variables, and step configurations.
When the editor opens an .aef file, it deserializes the embedded Java objects without validating their type or origin. An attacker who controls the file contents can embed a gadget chain that triggers code execution during the deserialization process itself, before the script is ever rendered in the editor UI.
Because exploitation requires user interaction and local access, the attack typically begins with social engineering, such as delivering the malicious .aef file by email or shared storage.
Root Cause
The root cause is the unrestricted use of Java object deserialization on attacker-controllable input. The affected code path does not enforce a class allow-list, does not use a ObjectInputFilter, and does not validate the structure of the serialized stream before instantiation. Any class available on the editor classpath, including known deserialization gadgets, can be reached during object graph reconstruction.
Attack Vector
The attack vector is local and requires user interaction. The attacker must convince a user with the Unified CCX Editor installed to download and open a crafted .aef file. No network listener is exploited, and no prior authentication to the Unified CCX server is required. Code executes with the privileges of the user account running the editor, which on administrator workstations frequently includes access to additional contact center infrastructure.
No public proof-of-concept exploit is currently available, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog. Refer to the Cisco Security Advisory for vendor technical details.
Detection Methods for CVE-2025-20275
Indicators of Compromise
- Unexpected .aef files arriving via email attachments, shared drives, or download directories on workstations where the Unified CCX Editor is installed.
- Child processes spawned by the Unified CCX Editor Java process (javaw.exe or java) such as cmd.exe, powershell.exe, or wscript.exe.
- Outbound network connections initiated by the editor process to non-Cisco infrastructure shortly after an .aef file is opened.
Detection Strategies
- Hunt for .aef files outside the standard Unified CCX repository paths and review their origin and integrity.
- Monitor for process lineage anomalies where the Unified CCX Editor parent process spawns shell interpreters or scripting hosts.
- Inspect serialized Java streams in .aef files for known gadget class signatures such as references to CommonsCollections, Spring, or Rome libraries.
Monitoring Recommendations
- Enable command-line and process-creation auditing on all workstations running the Unified CCX Editor.
- Forward editor application logs and endpoint telemetry to a central SIEM for correlation with email and file-share activity.
- Alert on file write events that create .aef files in user profile directories outside expected administrative workflows.
How to Mitigate CVE-2025-20275
Immediate Actions Required
- Identify all workstations running the Unified CCX Editor and inventory the installed version against the affected list.
- Apply the fixed software release referenced in the Cisco advisory as soon as it is available for your deployment.
- Instruct administrators to open .aef files only from trusted internal sources and never from email attachments or external storage.
Patch Information
Cisco has published fixed software in the Cisco Security Advisory cisco-sa-uccx-editor-rce-ezyYZte8. Customers should consult the advisory's Fixed Software section to map their current Unified CCX version to the appropriate upgrade path. No workaround that fully eliminates the vulnerability is documented by Cisco.
Workarounds
- Restrict the Unified CCX Editor application to a small set of hardened administrator workstations rather than general user endpoints.
- Use application allow-listing and file association controls to prevent .aef files from being opened automatically when double-clicked from untrusted locations.
- Run the editor under a low-privilege account that does not have administrative rights on the workstation or domain.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
