How severe is CVE-2025-66039?

CVE-2025-66039 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-66039 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-66039?

CVE-2025-66039 affects Sangoma Freepbx. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-66039?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2025-66039 have an EU (EUVD) identifier?

Yes. CVE-2025-66039 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-202329.

When was CVE-2025-66039 published?

CVE-2025-66039 was published on 2025-12-09 and last updated on 2026-06-17.

CVE-2025-66039

CVE-2025-66039 is a critical-severity vulnerability in Sangoma Freepbx with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 9.3
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-202329
Weakness: CWE-287
Affected product: Sangoma Freepbx
Published: 2025-12-09
Last modified: 2026-06-17

Description

FreePBX Endpoint Manager is a module for managing telephony endpoints in FreePBX systems. Versions are vulnerable to authentication bypass when the authentication type is set to "webserver." When providing an Authorization header with an arbitrary value, a session is associated with the target user regardless of valid credentials. This issue is fixed in versions 16.0.44 and 17.0.23.

Frequently asked questions

What is CVE-2025-66039?: FreePBX Endpoint Manager is a module for managing telephony endpoints in FreePBX systems. Versions are vulnerable to authentication bypass when the authentication type is set to "webserver." When providing an Authorization header with an arbitrary value, a session is associated with the target user regardless of valid credentials. This issue is fixed in versions 16.0.44 and 17.0.23.
How severe is CVE-2025-66039?: CVE-2025-66039 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-66039 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-66039?: CVE-2025-66039 affects Sangoma Freepbx. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-66039?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-66039 have an EU (EUVD) identifier?: Yes. CVE-2025-66039 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-202329.
When was CVE-2025-66039 published?: CVE-2025-66039 was published on 2025-12-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:sangoma:freepbx:*:*:*:*:*:*:*:*

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