How severe is CVE-2021-3176?

CVE-2021-3176 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-3176 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3176?

CVE-2021-3176 affects Mitel Businesscti Enterprise. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-3176?

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

When was CVE-2021-3176 published?

CVE-2021-3176 was published on 2021-01-29 and last updated on 2026-06-17.

CVE-2021-3176

CVE-2021-3176 is a high-severity vulnerability in Mitel Businesscti Enterprise with a CVSS 3.x base score of 8.0. 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-20.

Key facts

Severity: High (CVSS 3.x base score 8.0)
CVSS v2: 6.0
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mitel Businesscti Enterprise
Published: 2021-01-29
Last modified: 2026-06-17

Description

The chat window of the Mitel BusinessCTI Enterprise (MBC-E) Client for Windows before 6.4.15 and 7.x before 7.1.2 could allow an attacker to gain access to user information by sending certain code, due to improper input validation of http links. A successful exploit could allow an attacker to view user information and application data.

Frequently asked questions

What is CVE-2021-3176?: The chat window of the Mitel BusinessCTI Enterprise (MBC-E) Client for Windows before 6.4.15 and 7.x before 7.1.2 could allow an attacker to gain access to user information by sending certain code, due to improper input validation of http links. A successful exploit could allow an attacker to view user information and application data.
How severe is CVE-2021-3176?: CVE-2021-3176 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-3176 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3176?: CVE-2021-3176 affects Mitel Businesscti Enterprise. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-3176?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-3176 published?: CVE-2021-3176 was published on 2021-01-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mitel:businesscti_enterprise:*:*:*:*:*:windows:*:*

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