{"id":"CVE-2026-82427","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-82427","generatedAt":"2026-10-28T03:41:35.602Z","title":"A submitter could therefore use `../` segments to direct that delete-and-symlink operation at an arbitrary path, as the supervisor user, on every node the topology is scheduled onto.","description":"Description\n\nA topology's `topology.blobstore.map` lets the submitter choose a local name for each blob that the\nsupervisor localises. That name was used to build a path under the topology's working directory without\nnormalisation, in both `AsyncLocalizer` and `Container.createBlobstoreLinks`, and the symlink helper\nforce-deletes whatever already exists at the target before creating the link.\n\nA submitter could therefore use `../` segments to direct that delete-and-symlink operation at an arbitrary\npath, as the supervisor user, on every node the topology is scheduled onto. The consequences include\nrecursive deletion of supervisor-owned content and planting a symlink that causes a subsequent worker\nlaunch to execute attacker-chosen code as another tenant's operating-system user, which defeats the\nisolation that `supervisor.run.worker.as.user` is intended to provide.\n\nMitigation\n\nUpgrade to 3.1.0, where the resolved target must lie inside the expected root at both call sites.\n\nUsers who cannot upgrade immediately should restrict topology submission to trusted principals, and may\nreject submissions whose `topology.blobstore.map` entries contain path separators or `..` segments before\nthey reach Nimbus.\n\nCredit\n\nThe ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.","published":"2026-09-14T15:17:10.000Z","lastModified":"2026-09-14T20:58:48.000Z","status":"Deferred","sourceIdentifier":"security@apache.org","cvss":{"version":"3.1","score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-22"],"affected":[],"epss":{"score":0.00153,"percentile":0.04399,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.15%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://lists.apache.org/thread/o0j51w6m0qdmwypvzfnd8w97s7ysnmyj","source":"security@apache.org"},{"url":"http://www.openwall.com/lists/oss-security/2026/09/13/7","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-82427","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}