If the video came from an unknown sender or looks suspicious, it is safest to delete it without opening it.
If you are "looking into" this file due to security concerns or because it won't open, here is the relevant technical and safety information: 🛡️ Security Concerns: Malware & Exploits VID-20221228-WA0279.mp4
A high-severity flaw once allowed attackers to execute code via a malicious MP4. If the video came from an unknown sender
Can't download, open, or send media files | WhatsApp Help Center VID-20221228-WA0279.mp4
If your WhatsApp app and phone's operating system (Android/iOS) are up to date , these specific older vulnerabilities are patched and no longer a threat.