{"schema_version":"1.7.3","id":"GHSA-mxxc-p822-2hx9","published":"2026-01-26T23:26:56Z","modified":"2026-02-03T03:05:02.269547Z","aliases":["CVE-2026-24470","GO-2026-4378"],"summary":"Skipper Ingress Controller Allows Unauthorized Access to Internal Services via ExternalName","details":"### Impact\n\nWhen running Skipper as an Ingress controller, users with permissions to create an Ingress and a Service of type ExternalName can create routes that enable them to use Skipper's network access to reach internal services.\n\n### Patches\n\nhttps://github.com/zalando/skipper/releases/tag/v0.24.0 disables Kubernetes ExternalName by default.\n\n### Workarounds\n\nDevelopers can allow list targets of an ExternalName by using `-kubernetes-only-allowed-external-names=true` and allow list via regular expressions `-kubernetes-allowed-external-name '^[a-z][a-z0-9-.]+[.].allowed.example$'` \n\n### References\n\nhttps://kubernetes.io/docs/concepts/services-networking/service/#externalname","affected":[{"package":{"name":"github.com/zalando/skipper","ecosystem":"Go","purl":"pkg:golang/github.com/zalando/skipper"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.24.0"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-mxxc-p822-2hx9/GHSA-mxxc-p822-2hx9.json"}}],"references":[{"type":"WEB","url":"https://github.com/zalando/skipper/security/advisories/GHSA-mxxc-p822-2hx9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-24470"},{"type":"WEB","url":"https://github.com/zalando/skipper/commit/a4c87ce029a58eb8e1c2c1f93049194a39cf6219"},{"type":"PACKAGE","url":"https://github.com/zalando/skipper"},{"type":"WEB","url":"https://github.com/zalando/skipper/releases/tag/v0.24.0"},{"type":"WEB","url":"https://kubernetes.io/docs/concepts/services-networking/service/#externalname"}],"database_specific":{"cwe_ids":["CWE-441","CWE-918"],"github_reviewed":true,"github_reviewed_at":"2026-01-26T23:26:56Z","nvd_published_at":"2026-01-26T23:16:09Z","severity":"HIGH"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N"}]}