What is the UCF file format?
.UCF is a proprietary container format used by Cisco WebEx - UCF stands for Universal Communications Format. .ucf files can hold many different types of data, including movies, music, text documents, presentations, or web content, bundled for delivery within a WebEx session. The format was introduced by WebEx Communications (acquired by Cisco in 2007) and used primarily in legacy Meeting Center and Training Center sessions.
.ucf files cannot be opened manually or with general-purpose software; they are designed to be handled by the WebEx Universal Communications Toolkit or the legacy WebEx Player. The contents of .ucf files are processed by the application appropriate for each embedded data type. .ucf files were typically employed for exchanging rich media between videoconference attendees using WebEx, and it could be required by the meeting moderator that users verify they were equipped with software capable of handling the embedded content.
As of 2026, UCF is effectively a legacy format. The modern Cisco Webex platform no longer produces .ucf files; native file sharing and .arf recordings have replaced it. The old WebEx Player may still be available for download but the ecosystem is no longer actively maintained.
Security & safety
RISK: LOWUCF is a container format from Cisco; risk is mainly from embedded content (PowerPoint macros, Flash files). Flash EOL December 2020 - Flash content inside UCF is no longer executable in modern environments. Standard caution applies for files from unknown sources.
Format details
in a nutshell- Adobe AIR / SWF packager UCF (unrelated) - Adobe AIR uses a different UCF (Uncompressed Container Format) based on ZIP for packaging SWF + HTML apps - completely unrelated to Cisco WebEx UCF.
Programs that open UCF files
Windows2 apps
WebEx Player (Network Recording Player) - legacy
Free Download the legacy WebEx Network Recording Player from Cisco; open the .ucf file. Note: support for legacy formats may be limited.
7-Zip (if ZIP-based)
Open-source Try renaming .ucf to .zip and open with 7-Zip; if the container is ZIP-based this may expose embedded files. Not guaranteed. 
macOS1 app
WebEx Player (legacy, Mac)
Free Download Cisco's legacy recording player for macOS if available; compatibility with modern macOS not guaranteed. Technical details
deep spec| Container structure | Proprietary Cisco WebEx wrapper; internal structure undocumented, possibly ZIP-based |
| File encoding | Binary |
| Embedded content types | PowerPoint (.pptx/.ppt), Excel, video, audio, Flash files, web pages, WebEx .wrf recordings |
| Typical file size | 1 MB - 500 MB depending on embedded media |
| Compression | Likely per-entry compression (undocumented) |
| Encryption | None confirmed |
| MIME type | application/octet-stream (no registered MIME type) |
| Supported platforms | Windows, macOS |
| Creation tool | WebEx Universal Communications Toolkit (PowerPoint plug-in or WebEx Document Manager) |
| WebEx version era | WBS30 (WebEx Business Suite 30) and earlier |
| Current status | Legacy - modern Cisco Webex no longer produces or natively consumes .ucf files |
| Successor formats | .arf (WebEx Advanced Recording), .mp4 (modern Webex cloud recordings) |
| Released | circa 2000 (WebEx pre-Cisco era) |
| Latest version | unknown; format deprecated with legacy WebEx Player |
| Specification | www.cisco.com |
UCF conversions
Community Q&A
asked by usersNo questions yet - be the first to ask about UCF files.
