# Justice AV Solutions (JAVS) Viewer Installer Embedded Malicious Code · pwn.watch

> 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. Added to the CISA KEV catalog on 2024-05-29.

Page: https://pwn.watch/i/justice-av-solutions-viewer-cve-2024-4978 · generated 2026-10-22T22:00:08.805Z

## Status
- Severity: high · status: closed · patch: patched
- Product: Justice AV Solutions Viewer
- Started: 2024-05-23 · closed: 2024-05-29
- CVEs: CVE-2024-4978
- Affected: See vendor advisory (versions are not listed in the KEV record)
- Fixed in: See vendor advisory linked in sources

## Follow this incident
- RSS (one item per update): https://pwn.watch/i/justice-av-solutions-viewer-cve-2024-4978/feed.xml
- JSON Feed: https://pwn.watch/i/justice-av-solutions-viewer-cve-2024-4978/feed.json
- Full data (timeline, sources, posts, agentBrief): https://pwn.watch/i/justice-av-solutions-viewer-cve-2024-4978.json
- This file: https://pwn.watch/i/justice-av-solutions-viewer-cve-2024-4978/llms.txt

## Updates (newest first)
- 2024-05-29: CISA added CVE-2024-4978 to the KEV catalog (federal deadline 2024-06-19) (https://www.cisa.gov/known-exploited-vulnerabilities-catalog)
- 2024-05-23: CVE-2024-4978 published (https://nvd.nist.gov/vuln/detail/CVE-2024-4978)

## Fix brief
# Security brief: Justice AV Solutions (JAVS) Viewer Installer Embedded Malicious Code

Source: https://pwn.watch/i/justice-av-solutions-viewer-cve-2024-4978 · status: closed (closed May 29, 2024) · severity: high · updated May 29, 2024

## Patch status
**PATCHED: fixed releases exist. Upgrade to a fixed version.**

## What it is
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. Added to the CISA KEV catalog on 2024-05-29.

Severity detail: CVSS 8.4 (v3.1, CNA), actively exploited (CISA KEV)

- Product: Justice AV Solutions Viewer
- CVE / advisory ids: CVE-2024-4978

## Affected versions
- See vendor advisory (versions are not listed in the KEV record)

## Check whether you're affected
No generic command applies (the product is a hosted service, appliance or desktop app). Check the installed version in its admin UI / About screen and compare with the versions above.

## Fix
Upgrade to one of these fixed versions (or later on the same branch):
- See vendor advisory linked in sources

After upgrading, re-run the checks above and redeploy/restart the affected services.

## Latest updates
- May 29, 2024: CISA added CVE-2024-4978 to the KEV catalog (federal deadline 2024-06-19)
- May 23, 2024: CVE-2024-4978 published

## Advisories
- [Justice AV Solutions advisory: CVE-2024-4978](https://www.rapid7.com/blog/post/2024/05/23/cve-2024-4978-backdoored-justice-av-solutions-viewer-software-used-in-apparent-supply-chain-attack#remediation) (Justice AV Solutions)
- [Justice AV Solutions advisory: CVE-2024-4978](https://www.javs.com/downloads) (Justice AV Solutions)
- [NVD: CVE-2024-4978](https://nvd.nist.gov/vuln/detail/CVE-2024-4978) (NVD)
- [CISA Known Exploited Vulnerabilities Catalog](https://www.cisa.gov/known-exploited-vulnerabilities-catalog) (CISA)

## Caveats
Derived from the CISA KEV JSON feed (catalogVersion 2026.10.21); CVSS from the CVE record (cveawg.mitre.org). startedAt is the CVE publication date when it fell in 2024 before the KEV listing, else the KEV dateAdded; exploitation may have begun earlier. closedAt is the KEV listing date (a fix or mitigation was available then unless noted).

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Machine-readable: https://pwn.watch/i/justice-av-solutions-viewer-cve-2024-4978.json · all incidents: https://pwn.watch/incidents.json. Verify against the vendor advisory before changing production systems.