How severe is CVE-2016-6440?

CVE-2016-6440 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2016-6440 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-6440?

CVE-2016-6440 affects Cisco Unified Communications Manager. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-6440?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2016-6440 published?

CVE-2016-6440 was published on 2016-10-27 and last updated on 2026-06-17.

CVE-2016-6440

CVE-2016-6440 is a medium-severity vulnerability in Cisco Unified Communications Manager with a CVSS 3.x base score of 6.5. 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: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Unified Communications Manager
Published: 2016-10-27
Last modified: 2026-06-17

Description

The Cisco Unified Communications Manager (CUCM) may be vulnerable to data that can be displayed inside an iframe within a web page, which in turn could lead to a clickjacking attack. More Information: CSCuz64683 CSCuz64698. Known Affected Releases: 11.0(1.10000.10), 11.5(1.10000.6), 11.5(0.99838.4). Known Fixed Releases: 11.0(1.22048.1), 11.5(0.98000.1070), 11.5(0.98000.284)11.5(0.98000.346), 11.5(0.98000.768), 11.5(1.10000.3), 11.5(1.10000.6), 11.5(2.10000.2).

Frequently asked questions

What is CVE-2016-6440?: The Cisco Unified Communications Manager (CUCM) may be vulnerable to data that can be displayed inside an iframe within a web page, which in turn could lead to a clickjacking attack. More Information: CSCuz64683 CSCuz64698. Known Affected Releases: 11.0(1.10000.10), 11.5(1.10000.6), 11.5(0.99838.4). Known Fixed Releases: 11.0(1.22048.1), 11.5(0.98000.1070), 11.5(0.98000.284)11.5(0.98000.346), 11.5(0.98000.768), 11.5(1.10000.3), 11.5(1.10000.6), 11.5(2.10000.2).
How severe is CVE-2016-6440?: CVE-2016-6440 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2016-6440 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-6440?: CVE-2016-6440 affects Cisco Unified Communications Manager. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-6440?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-6440 published?: CVE-2016-6440 was published on 2016-10-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:cisco:unified_communications_manager:11.5\(0.99838.4\):*:*:*:*:*:*:*

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