An issue was discovered in FusionPBX before 4.5.30.

published 2021-11-05 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-30341

cvss: 8.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.0%; EPSS 1.0% chance of exploitation in 30 days, percentile 62%
public exploits: 0; none known

An issue was discovered in FusionPBX before 4.5.30. The fax_post_size may have risky characters (it is not constrained to preset values).

Patch / fix

fixed in 1 links 1

fusionpbx fusionpbx 4.5.30

github.com/fusionpbx/fusionpbx@0377b21 commit

Exploit prediction

0.97% chance of exploitation in the next 30 days, higher than 62% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	6.5	AV:N/AC:L/Au:S/C:P/I:P/A:P

Classification

Weakness

CWE-20 Improper Input Validation

References

github.com /fusionpbx/fusionpbx/commit/0377b2152c0e59c8f35297f9a9b6ee335a62d963
patch, third-party-advisory

Sources

CVE List CVE-2021-43406
NVD CVE-2021-43406

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary