---
id: "CVE-2024-4978"
kind: "vulnerability"
aliases: ["CVE-2024-4978"]
title: "javs viewer: Justice AV Solutions Viewer Setup 8.3.7.250-1 contains a malicious binary when executed and is signed with an\u2026"
severity: "critical"
cvss: 8.7
epss: null
exploited: true
status: "open"
category: "vendor"
products: [{"name": "Justice AV Solutions Viewer", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "javs viewer", "fixed": [], "affected": "= 8.3.7.250", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "javs-viewer", "vendor", "windows"]
not_affected_if: ["not-installed"]
published_at: "2024-05-23T02:15:09+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T22:29:05+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2024-4978", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-4978", "first_seen_at": "2026-10-23T22:29:05+00:00"}]
---

# javs viewer: Justice AV Solutions Viewer Setup 8.3.7.250-1 contains a malicious binary when executed and is signed with an…

The JAVS Viewer installer ships a trojanized ffmpeg.exe (named fffmpeg.exe) that opens a backdoor connection to a malicious command-and-control server when run. An attacker who gets the installed binary onto a machine gets remote access to it.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Justice AV Solutions Viewer affected ? fixed ?
- vendor:javs viewer affected = 8.3.7.250 fixed ?

## How to check

Search the machine for fffmpeg.exe with SHA256 421a4ad2615941b177b6ec4ab5e239c14e62af2ab07c6df1741e2a62223223c4

## Fix

Apply the vendor mitigations or stop using JAVS Viewer, per the CISA required action

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2024-4978
- 2026-10-23T22:29:05+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2024-4978

## From the sources

Justice AV Solutions (JAVS) Viewer installer contains a malicious version of ffmpeg.exe, named fffmpeg.exe (SHA256: 421a4ad2615941b177b6ec4ab5e239c14e62af2ab07c6df1741e2a62223223c4). When run, this creates a backdoor connection to a malicious C2 server.

CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_