{"schema_version":"1.8.0","id":"CVE-2021-25737","published":"2021-09-06T12:15:07.673Z","modified":"2026-08-07T16:50:50.489017Z","aliases":["GHSA-mfv7-gq43-w965","GO-2022-0908"],"related":["openSUSE-SU-2025:15424-1"],"details":"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.","affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/kubernetes/kubelet","events":[{"introduced":"250a1838aa2c492c9096ff86558515b8639d7e87"},{"fixed":"d0d3bc6b038cb8f886d5cf3c175bffc0cb1dbf00"},{"introduced":"1af8853567a0faecc59fbc4d7d2ddc9359ddde83"},{"fixed":"ea1348bf4a58d089e74ac7def7f855945a2c0bbb"},{"introduced":"30b4cd52c54df86ed93459ba84b3e61877fc28ea"},{"fixed":"cf20a01fcb9ee37249f8c9d3b386cbfdfefe7724"},{"introduced":"2f96697a6b8649844ec80a9bbe6d7cde3b197f5b"},{"last_affected":"2f96697a6b8649844ec80a9bbe6d7cde3b197f5b"}],"database_specific":{"cpe":["cpe:2.3:a:kubernetes:kubernetes:*:*:*:*:*:*:*:*","cpe:2.3:a:kubernetes:kubernetes:1.21.0:-:*:*:*:*:*:*"],"extracted_events":[{"introduced":"1.16.0"},{"fixed":"1.18.19"},{"introduced":"1.19.0"},{"fixed":"1.19.10"},{"introduced":"1.20.0"},{"fixed":"1.20.7"},{"introduced":"1.21.0-NA"},{"last_affected":"1.21.0-NA"}],"source":["CPE_RANGE","CPE_STRING"]}}],"versions":["1.21.0-NA","v0.21.0","kubernetes-1.21.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-25737.json"}},{"ranges":[{"type":"GIT","repo":"https://github.com/kubernetes/kubernetes","events":[{"introduced":"2bd9643cee5b3b3a5ecbd3af49d09018f0773c77"},{"fixed":"ac0cc736d0018d817c763083945e4db863168d12"},{"introduced":"e19964183377d0ec2052d1f1fa930c4d7575bd50"},{"fixed":"98d5dc5d36d34a7ee13368a7893dcb400ec4e566"},{"introduced":"af46c47ce925f4c4ad5cc8d1fca46c7b77d13b38"},{"fixed":"132a687512d7fb058d0f5890f07d4121b3f0a2e2"},{"introduced":"cb303e613a121a29364f75cc67d3d580833a7479"},{"last_affected":"cb303e613a121a29364f75cc67d3d580833a7479"}],"database_specific":{"cpe":["cpe:2.3:a:kubernetes:kubernetes:*:*:*:*:*:*:*:*","cpe:2.3:a:kubernetes:kubernetes:1.21.0:-:*:*:*:*:*:*"],"extracted_events":[{"introduced":"1.16.0"},{"fixed":"1.18.19"},{"introduced":"1.19.0"},{"fixed":"1.19.10"},{"introduced":"1.20.0"},{"fixed":"1.20.7"},{"introduced":"1.21.0-NA"},{"last_affected":"1.21.0-NA"}],"source":["CPE_RANGE","CPE_STRING"]}}],"versions":["1.21.0-NA","v1.20.7-rc.0","v1.20.6","v1.21.0","v1.20.6-rc.0","v1.19.10-rc.0","v1.20.5","v1.19.9","v1.20.5-rc.0","v1.20.4","v1.19.9-rc.0","v1.20.4-rc.0","v1.20.3","v1.19.8","v1.20.3-rc.0","v1.19.8-rc.0","v1.20.2","v1.19.7","v1.20.2-rc.0","v1.19.7-rc.0","v1.19.6","v1.20.1","v1.19.6-rc.1","v1.20.1-rc.1","v1.19.6-rc.0","v1.19.5","v1.20.1-rc.0","v1.20.0","v1.19.5-rc.0","v1.19.4","v1.19.4-rc.0","v1.19.3","v1.19.3-rc.0","v1.19.2","v1.19.2-rc.0","v1.19.1","v1.19.1-rc.0","v1.19.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-25737.json"}}],"references":[{"type":"ADVISORY","url":"https://groups.google.com/g/kubernetes-security-announce/c/xAiN3924thY"},{"type":"ADVISORY","url":"https://security.netapp.com/advisory/ntap-20211004-0004/"},{"type":"FIX","url":"https://github.com/kubernetes/kubernetes/issues/102106"}],"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N"}]}