Medium severity · published Feb 25, 2026
CVE-2026-20091
Cisco UCS Manager and FXOS Software Stored Cross-Site Scripting Vulnerability
4.8
CVSS
0.2%
EPSS
No
On KEV
Description
A vulnerability in the web-based management interface of Cisco FXOS Software and Cisco UCS Manager Software could allow an authenticated, remote attacker to conduct a stored cross-site scripting (XSS) attack against a user of the interface. This vulnerability is due to insufficient validation of user-supplied input by the web-based management interface of an affected system. An attacker could exploit this vulnerability by injecting malicious data into specific pages of the interface. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface or access sensitive, browser-based information. To exploit this vulnerability, the attacker must have valid credentials for a user account with the role of Administrator or AAA Administrator. 
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 10% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CF
Cisco Firepower Extensible Operating System (FXOS) · Cisco
2.14.1.131; 2.14.1.143; 2.14.1.163; 2.14.1.167; 2.16.0.128 · source: vendor
CS
Cisco Secure Firewall Adaptive Security Appliance (ASA) Software · Cisco
9.12.2; 9.12.1; 9.12.3; 9.12.4; 9.12.3.2; 9.12.3.12; +34 more · source: vendor
CU
Cisco Unified Computing System (Managed) · Cisco
4.0(4h); 4.1(1a); 4.0(1c); 4.0(4a); 4.0(1a); 4.0(1d); +34 more · source: vendor
Affected product
CF
Cisco Firepower Extensible Operating System (FXOS)
Cisco
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