High severity · published May 6, 2026
CVE-2026-20034
Cisco Unity Connection Remote Code Execution Vulnerability
8.8
CVSS
0.7%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 53% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CU
Cisco Unity Connection · Cisco
12.5(1); 12.5(1)SU1; 12.5(1)SU2; 12.5(1)SU3; 12.5(1)SU4; 14; +15 more · source: vendor
UC
Unity Connection · Cisco
before 14.0; 14.0; 14su1; 14su2; 14su3; 14su4; +4 more · source: NVD
Affected product
CU
Cisco Unity Connection
Cisco
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