How severe is CVE-2016-6426?

CVE-2016-6426 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2016-6426 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-6426?

CVE-2016-6426 primarily affects Cisco Unified Contact Center Express. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-6426?

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-2016-6426 published?

CVE-2016-6426 was published on 2016-10-05 and last updated on 2026-06-17.

CVE-2016-6426

CVE-2016-6426 is a high-severity vulnerability in Cisco Unified Contact Center Express with a CVSS 3.x base score of 7.5. 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: High (CVSS 3.x base score 7.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Unified Contact Center Express
Published: 2016-10-05
Last modified: 2026-06-17

Description

The j_spring_security_switch_user function in Cisco Unified Intelligence Center (CUIC) 8.5.4 through 9.1(1), as used in Unified Contact Center Express 10.0(1) through 11.0(1), allows remote attackers to create user accounts by visiting an unspecified web page, aka Bug IDs CSCuy75027 and CSCuy81653.

Frequently asked questions

What is CVE-2016-6426?: The j_spring_security_switch_user function in Cisco Unified Intelligence Center (CUIC) 8.5.4 through 9.1(1), as used in Unified Contact Center Express 10.0(1) through 11.0(1), allows remote attackers to create user accounts by visiting an unspecified web page, aka Bug IDs CSCuy75027 and CSCuy81653.
How severe is CVE-2016-6426?: CVE-2016-6426 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2016-6426 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-6426?: CVE-2016-6426 primarily affects Cisco Unified Contact Center Express. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-6426?: 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-2016-6426 published?: CVE-2016-6426 was published on 2016-10-05 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:cisco:unified_contact_center_express:10.0\(1\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_contact_center_express:10.5\(1\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_contact_center_express:10.6\(1\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_contact_center_express:11.0\(1\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_intelligence_center:8.5.4:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_intelligence_center:9.0\(2\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_intelligence_center:9.1\(1\):*:*:*:*:*:*:*

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