What is CVE-2018-15891?

CVE-2018-15891 is a medium-severity vulnerability in Freepbx, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2019-06-20.

How severe is CVE-2018-15891?

Medium severity. CVSS v3 base score is 4.8 out of 10.

XSS in Freepbx

CVE-2018-15891

An issue was discovered in FreePBX core before 3.0.122.43, 14.0.18.34, and 5.0.1beta4. By crafting a request for adding Asterisk modules, an attacker is able to store JavaScript commands in a module name.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2019-06-20 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.006 (44.6th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 44.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Freepbx — versions 15.0.1
Sangoma Freepbx — versions 15.0.1

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

www.freepbx.org/ (Product)
wiki.freepbx.org/display/FOP/2018-09-11+Core+Stored+XSS (Vendor Advisory)

Frequently asked questions

What is CVE-2018-15891?: CVE-2018-15891 is a medium-severity vulnerability in Freepbx, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2019-06-20.
How severe is CVE-2018-15891?: Medium severity. CVSS v3 base score is 4.8 out of 10.