CVE-2026-20034
CVE-2026-20034 is a high-severity vulnerability in Cisco Unity Connection with a CVSS 3.x base score of 8.8. 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-35.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- EPSS exploit prediction: 1% (49th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-27847
- Weakness: CWE-35
- Affected product: Cisco Unity Connection
- Published:
- Last modified:
Description
A vulnerability in the web-based management interface of Cisco Unity Connection could allow an authenticated, remote attacker to execute arbitrary code on an affected device. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by submitting a crafted API request. A successful exploit could allow the attacker to execute arbitrary code as root, possibly resulting in the complete compromise of a targeted device. To exploit this vulnerability, the attacker must have valid user credentials on the affected device.
Frequently asked questions
- What is CVE-2026-20034?
- A vulnerability in the web-based management interface of Cisco Unity Connection could allow an authenticated, remote attacker to execute arbitrary code on an affected device. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by submitting a crafted API request. A successful exploit could allow the attacker to execute arbitrary code as root, possibly resulting in the complete compromise of a targeted device. To exploit this vulnerability, the attacker must have valid user credentials on the affected device.
- How severe is CVE-2026-20034?
- CVE-2026-20034 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-20034 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-20034?
- CVE-2026-20034 primarily affects Cisco Unity Connection. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2026-20034?
- 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.
- Does CVE-2026-20034 have an EU (EUVD) identifier?
- Yes. CVE-2026-20034 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27847.
- When was CVE-2026-20034 published?
- CVE-2026-20034 was published on 2026-05-06 and last updated on 2026-07-01.
References
Affected products (10)
- cpe:2.3:a:cisco:unity_connection:*:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:unity_connection:14.0:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:unity_connection:14su1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:unity_connection:14su2:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:unity_connection:14su3:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:unity_connection:14su4:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:unity_connection:15.0:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:unity_connection:15su1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:unity_connection:15su2:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:unity_connection:15su3:*:*:*:*:*:*:*
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