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Vulnerability record · CVE-2021-43405 · published 5 November 2021

CVE-2021-43405: Fusionpbx vulnerability

Fusionpbx · Fusionpbx

An issue was discovered in FusionPBX before 4.5.30. The fax_extension may have risky characters (it is not constrained to be numeric).

8.8 CVSS 3.1 High EPSS 36% · top 1.6%
8.8CVSS 3.1 base score, v2 6.5
36%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

An issue was discovered in FusionPBX before 4.5.30. The fax_extension may have risky characters (it is not constrained to be numeric).

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://packetstormsecurity.com/files/164795/FusionPBX-4.5.29-Remote-Code-Execution.html ExploitThird Party Advisory
https://github.com/fusionpbx/fusionpbx/commit/2d2869c1a1e874c46a8c3c5475614ce769bbbd59 PatchThird Party Advisory
http://packetstormsecurity.com/files/164795/FusionPBX-4.5.29-Remote-Code-Execution.html ExploitThird Party Advisory
https://github.com/fusionpbx/fusionpbx/commit/2d2869c1a1e874c46a8c3c5475614ce769bbbd59 PatchThird Party Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2022-35153Fusionpbx vulnerabilityFusionPBX 5.0.1 was discovered to contain a command injection vulnerability via /fax/fax_send.php.EPSS 1.8%9.8CVE-2022-28055Fusionpbx os command injection vulnerabilityFusionpbx v4.4 and below contains a command injection vulnerability via the download email logs function.EPSS 1.5%8.8CVE-2021-43404Fusionpbx vulnerabilityAn issue was discovered in FusionPBX before 4.5.30. The FAX file name may have risky characters.EPSS 0.97%8.8CVE-2021-43406Fusionpbx improper input validation vulnerabilityAn issue was discovered in FusionPBX before 4.5.30. The fax_post_size may have risky characters (it is not constrained to preset values).EPSS 0.97%8.8CVE-2019-16964Fusionpbx os command injection vulnerabilityapp/call_centers/cmd.php in the Call Center Queue Module in FusionPBX up to 4.5.7 suffers from a command injection vulnerability due to a lack of inp…EPSS 2.0%8.8CVE-2019-16980Fusionpbx sql injection vulnerabilityIn FusionPBX up to v4.5.7, the file app\call_broadcast\call_broadcast_edit.php uses an unsanitized "id" variable coming from the URL in an unparamete…EPSS 1.2%8.8CVE-2019-15029Fusionpbx os command injection vulnerabilityFusionPBX 4.4.8 allows an attacker to execute arbitrary system commands by submitting a malicious command to the service_edit.php file (which will in…EPSS 12%8.8CVE-2019-11409FusionPBX Operator Panel exec.php command injectionFusionPBX 4.4.3's Operator Panel module (app/operator_panel/exec.php) fails to validate input, allowing OS command injection. An authenticated non-ad…EPSS 87%analysed

Source: NIST National Vulnerability Database (record CVE-2021-43405), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.