CVE-2019-16990 — In FusionPBX up to v4

In FusionPBX up to v4.5.7, the file app/music_on_hold/music_on_hold.php uses an unsanitized "file" variable coming from the URL, which takes any pathname (base64 encoded) and allows a download of it.

01What is this vulnerability?

In FusionPBX up to v4.5.7, the file app/music_on_hold/music_on_hold.php uses an unsanitized "file" variable coming from the URL, which takes any pathname (base64 encoded) and allows a download of it.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2019-10-21T14:20:53.000Z
• Last modified: 2024-08-05T01:24:48.678Z

09References

• github.com — https://github.com/fusionpbx/fusionpbx/commit/95ed18aa9d781f232f5686a9027bb6f677…
• resp3ctblog.wordpress.com — https://resp3ctblog.wordpress.com/2019/10/19/fusionpbx-path-traversal-3/