{"cve":"CVE-2026-82427","nvd":{"published":"2026-09-14T15:17:09.553","modified":"2026-09-14T20:58:48.430","status":"Deferred","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-22"],"references":["https://lists.apache.org/thread/o0j51w6m0qdmwypvzfnd8w97s7ysnmyj","http://www.openwall.com/lists/oss-security/2026/09/13/7"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:53:43.293028046+00:00"},"epss":{"cve":"CVE-2026-82427","score":0.00153,"percentile":0.04434,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}