High severity · published Oct 6, 2026
CVE-2026-101158
A missing input validation vulnerability in the Fileserver upload API allows an authenticated attacker with file upload privileges to execute stored cross-site scripting (XSS)
8.4
CVSS
0.3%
EPSS
No
On KEV
Description
A missing input validation vulnerability in the Fileserver upload API allows an authenticated attacker with file upload privileges to execute stored cross-site scripting (XSS). Successful exploitation could enable the attacker to hijack another CloudVision user's web session, potentially granting full access to their account and administrative permissions.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 21% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CP
CloudVision Portal · Arista Networks
2026.2.0; 2026.1.0 through 2026.1.2; 2025.3.0 through 2025.3.3; 1.0.0 before 2025.3.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-101158
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-101158
vendor-advisory
https://www.arista.com/en/support/advisories-notices/security-advisory/24801-security-advisory-0185
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