Medium severity · published Sep 16, 2025
CVE-2025-9708
Kubernetes C# Client: improper certificate validation in custom CA mode may lead to man-in-the-middle attacks
6.8
CVSS
0.3%
EPSS
No
On KEV
Description
A vulnerability exists in the Kubernetes C# client where the certificate validation logic accepts properly constructed certificates from any Certificate Authority (CA) without properly verifying the trust chain. This flaw allows a malicious actor to present a forged certificate and potentially intercept or manipulate communication with the Kubernetes API server, leading to possible man-in-the-middle attacks and API impersonation.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 24% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KC
Kubernetes CSharp Client · Kubernetes
through 17.0.13 · source: vendor