{"id":"GHSA-8wcj-mfrc-jx5q","summary":"Fission builder pods auto-mount the fission-builder ServiceAccount token in the user-supplied builder container","details":"### Summary\n\nFission builder pods were created with `ServiceAccountName: fission-builder` and no `AutomountServiceAccountToken: false`, so the kubelet auto-mounted the service-account token into every container in the pod — including the\nuser-supplied builder image.\n\n### Details\n\nThe user controls the builder container image, command, and podspec through `Environment.spec.builder.image` / `.container` / `.podspec`. With the SA token auto-mounted at `/var/run/secrets/kubernetes.io/serviceaccount/token` inside that\n container, any code running there inherited the `fission-builder` identity. The `fission-builder` SA holds namespace-wide `get` on `secrets` and `configmaps` (`pkg/utils/serviceaccount.go`), so the user-controlled builder container\ncould read every Secret in the builder namespace by name.\n\nThis is the buildermgr sibling of GHSA-85g2-pmrx-r49q (CVE-2026-46617), whose fix suppressed the SA-token automount on function runtime pods but did not cover the structurally identical primitive in `pkg/buildermgr/envwatcher.go`.\n\n### Impact\n\nA subject with `create`/`update` on `Environment` CRDs in a namespace observed by the buildermgr could read every Secret and ConfigMap in the builder namespace via the auto-mounted `fission-builder` token.\n\n### Fix\n\nFixed in [#3390](https://github.com/fission/fission/pull/3390) and released in [v1.24.0](https://github.com/fission/fission/releases/tag/v1.24.0). In `createBuilderDeployment`:\n\n- Set pod-level `AutomountServiceAccountToken=false` on the initial PodSpec and add the projected fetcher SA-token volume.\n- Re-clamp `AutomountServiceAccountToken=false` after every `MergePodSpec` call so a user-supplied podspec cannot restore the kubelet automount.\n- Mount the token via a projected volume on the fetcher sidecar only, so the legitimate build → archive-upload flow keeps its cluster API access.\n\nReuses the projected-volume helpers from `pkg/executor/util/satoken.go` introduced by the GHSA-85g2-pmrx-r49q fix.\n\n### Behavioural change\n\nThe user-supplied builder container no longer receives an auto-mounted SA token. The fetcher sidecar still gets its token via a projected volume.","aliases":["CVE-2026-50565","GO-2026-5850"],"modified":"2026-07-07T16:11:28.677449689Z","published":"2026-06-30T18:20:03Z","database_specific":{"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2026-06-30T18:20:03Z","nvd_published_at":"2026-06-10T18:17:12Z","cwe_ids":["CWE-250","CWE-269","CWE-538"]},"references":[{"type":"WEB","url":"https://github.com/fission/fission/security/advisories/GHSA-8wcj-mfrc-jx5q"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-50565"},{"type":"WEB","url":"https://github.com/fission/fission/pull/3390"},{"type":"WEB","url":"https://github.com/fission/fission/commit/8fa799417c77ce8a0189d9858bfe11ece29b84a6"},{"type":"PACKAGE","url":"https://github.com/fission/fission"},{"type":"WEB","url":"https://github.com/fission/fission/releases/tag/v1.24.0"}],"affected":[{"package":{"name":"github.com/fission/fission","ecosystem":"Go","purl":"pkg:golang/github.com/fission/fission"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.24.0"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-8wcj-mfrc-jx5q/GHSA-8wcj-mfrc-jx5q.json","last_known_affected_version_range":"\u003c= 1.23.0"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N"}]}