Medium severity · published Sep 6, 2021
CVE-2021-25737
A security issue was discovered in Kubernetes where a user may be able to redirect pod traffic to private networks on a Node
4.8
CVSS
1.3%
EPSS
No
On KEV
Description
A security issue was discovered in Kubernetes where a user may be able to redirect pod traffic to private networks on a Node. Kubernetes already prevents creation of Endpoint IPs in the localhost or link-local range, but the same validation was not performed on EndpointSlice IPs.
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)1.3% · higher than 71% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KU
Kubernetes · Kubernetes
1.16.0 before 1.18.19; 1.19.0 before 1.19.10; 1.20.0 before 1.20.7; 1.21.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-25737
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-25737
Patch
https://github.com/kubernetes/kubernetes/issues/102106
Mailing List
https://groups.google.com/g/kubernetes-security-announce/c/xAiN3924thY
Third Party Advisory
https://security.netapp.com/advisory/ntap-20211004-0004/
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