What is CVE-2021-46558?

CVE-2021-46558 is a medium-severity vulnerability in Issabel Pbx, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2022-02-15.

How severe is CVE-2021-46558?

Medium severity. CVSS v3 base score is 5.4 out of 10.

Is CVE-2021-46558 known to be exploited?

3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

XSS in Issabel Pbx

CVE-2021-46558

Multiple cross-site scripting (XSS) vulnerabilities in the Add User module of Issabel PBX 20200102 allows attackers to execute arbitrary web scripts or HTML via a crafted payload inserted into the username and password fields.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2022-02-15 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.006 (44.6th percentile), scored 2026-09-30.

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

Issabel Pbx — versions 20200102

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

Public proof-of-concept exploits

References

github.com/Zeyad-Azima/Issabel-stored-XSS (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2021-46558?: CVE-2021-46558 is a medium-severity vulnerability in Issabel Pbx, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2022-02-15.
How severe is CVE-2021-46558?: Medium severity. CVSS v3 base score is 5.4 out of 10.
Is CVE-2021-46558 known to be exploited?: 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.