What’s Vulnerable › Vulnerabilities

CVE-2021-43406

• Severity: high (CVSS 8.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.0% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-11-05 · updated 2026-06-17
• Weakness: CWE-20

Description

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).

Affected products

• fusionpbx: before 4.5.30 — fixed in 4.5.30

How to fix

Upgrade to a fixed version: fusionpbx 4.5.30. Check the vendor advisory for mitigations.

References

• https://github.com/fusionpbx/fusionpbx/commit/0377b2152c0e59c8f35297f9a9b6ee335a62d963
• https://github.com/fusionpbx/fusionpbx/commit/0377b2152c0e59c8f35297f9a9b6ee335a62d963

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