{"api_version":"1","generated_at":"2026-11-10T07:37:42+00:00","cve":"CVE-2026-82440","urls":{"html":"https://cve.report/CVE-2026-82440","api":"https://cve.report/api/cve/CVE-2026-82440.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-82440","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-82440"},"summary":{"title":"Apache Storm Nimbus: Submitter-Controlled Class Instantiation in Nimbus via a Fail-Open Scheduler Strategy Allowlist","description":"Description\n\nNimbus instantiates the class named by a topology's `topology.scheduler.strategy` when scheduling it. The\nallowlist intended to constrain that choice, `nimbus.scheduler.strategy.class.whitelist`, was treated as\n\"allow any class\" when unset, and it had no entry in the shipped `defaults.yaml`, so unset was the shipped\nstate. An authenticated submitter could therefore cause Nimbus to instantiate any class on the Nimbus\nclasspath that has a no-argument constructor.\n\nStorm's own production artifacts contain classes with side effects suitable for this: instantiating\n`org.apache.storm.testing.InProcessZookeeper` starts a ZooKeeper server with its own threads and sockets\nand nothing closes it, and `org.apache.storm.LocalCluster` behaves similarly. Repeated submissions\ntherefore consume threads, sockets and memory in the most privileged daemon in the cluster.\n\nMitigation\n\nUpgrade to 3.1.0, where an unset allowlist means the strategies shipped with Storm rather than any class.\n\nNote that this is a behaviour change: a cluster running an out-of-tree scheduler strategy without an\nexplicit allowlist will have those topologies refused until the class is added to\n`nimbus.scheduler.strategy.class.whitelist`. The rejection message names the refused class and the\nconfiguration key.\n\nUsers who cannot upgrade immediately should set `nimbus.scheduler.strategy.class.whitelist` explicitly to\nthe strategies they intend to permit.","state":"PUBLISHED","assigner":"apache","published_at":"2026-11-09 10:17:11","updated_at":"2026-11-09 11:17:26"},"problem_types":["CWE-470","CWE-470 CWE-470 Use of Externally-Controlled input to select classes or code ('unsafe reflection')"],"metrics":[],"references":[{"url":"https://lists.apache.org/thread.html/hxcyk1vg9qx8bzos8g3kx91nz8d23jgt","name":"https://lists.apache.org/thread.html/hxcyk1vg9qx8bzos8g3kx91nz8d23jgt","refsource":"security@apache.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"http://www.openwall.com/lists/oss-security/2026/11/09/2","name":"http://www.openwall.com/lists/oss-security/2026/11/09/2","refsource":"af854a3a-2127-422b-91ae-364da2661108","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-82440","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-82440","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Apache Software Foundation","product":"Apache Storm Nimbus","version":"affected 3.0.0 3.1.0 semver","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[{"source":"CNA","value":"The ASF using Claude Agents","lang":"en"}],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"providerMetadata":{"dateUpdated":"2026-11-09T10:13:16.862Z","orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE"},"references":[{"url":"http://www.openwall.com/lists/oss-security/2026/11/09/2"}],"title":"CVE Program Container"}],"cna":{"affected":[{"collectionURL":"https://repo.maven.apache.org/maven2","defaultStatus":"unaffected","packageName":"org.apache.storm:storm-client","packageURL":"pkg:maven/org.apache.storm/storm-client","product":"Apache Storm Nimbus","vendor":"Apache Software Foundation","versions":[{"lessThan":"3.1.0","status":"affected","version":"3.0.0","versionType":"semver"}]}],"credits":[{"lang":"en","type":"finder","value":"The ASF using Claude Agents"}],"descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"<b>Description</b><br><br>Nimbus instantiates the class named by a topology's `topology.scheduler.strategy` when scheduling it. The<br>allowlist intended to constrain that choice, `nimbus.scheduler.strategy.class.whitelist`, was treated as<br>\"allow any class\" when unset, and it had no entry in the shipped `defaults.yaml`, so unset was the shipped<br>state. An authenticated submitter could therefore cause Nimbus to instantiate any class on the Nimbus<br>classpath that has a no-argument constructor.<br><br>Storm's own production artifacts contain classes with side effects suitable for this: instantiating<br>`org.apache.storm.testing.InProcessZookeeper` starts a ZooKeeper server with its own threads and sockets<br>and nothing closes it, and `org.apache.storm.LocalCluster` behaves similarly. Repeated submissions<br>therefore consume threads, sockets and memory in the most privileged daemon in the cluster.<br><br><div><b>Mitigation</b><br><br>Upgrade to 3.1.0, where an unset allowlist means the strategies shipped with Storm rather than any class.<br><br>Note that this is a behaviour change: a cluster running an out-of-tree scheduler strategy without an<br>explicit allowlist will have those topologies refused until the class is added to<br>`nimbus.scheduler.strategy.class.whitelist`. The rejection message names the refused class and the<br>configuration key.<br><br>Users who cannot upgrade immediately should set `nimbus.scheduler.strategy.class.whitelist` explicitly to<br>the strategies they intend to permit.</div>"}],"value":"Description\n\nNimbus instantiates the class named by a topology's `topology.scheduler.strategy` when scheduling it. The\nallowlist intended to constrain that choice, `nimbus.scheduler.strategy.class.whitelist`, was treated as\n\"allow any class\" when unset, and it had no entry in the shipped `defaults.yaml`, so unset was the shipped\nstate. An authenticated submitter could therefore cause Nimbus to instantiate any class on the Nimbus\nclasspath that has a no-argument constructor.\n\nStorm's own production artifacts contain classes with side effects suitable for this: instantiating\n`org.apache.storm.testing.InProcessZookeeper` starts a ZooKeeper server with its own threads and sockets\nand nothing closes it, and `org.apache.storm.LocalCluster` behaves similarly. Repeated submissions\ntherefore consume threads, sockets and memory in the most privileged daemon in the cluster.\n\nMitigation\n\nUpgrade to 3.1.0, where an unset allowlist means the strategies shipped with Storm rather than any class.\n\nNote that this is a behaviour change: a cluster running an out-of-tree scheduler strategy without an\nexplicit allowlist will have those topologies refused until the class is added to\n`nimbus.scheduler.strategy.class.whitelist`. The rejection message names the refused class and the\nconfiguration key.\n\nUsers who cannot upgrade immediately should set `nimbus.scheduler.strategy.class.whitelist` explicitly to\nthe strategies they intend to permit."}],"metrics":[{"other":{"content":{"text":"moderate"},"type":"Textual description of severity"},"scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-470","description":"CWE-470 Use of Externally-Controlled input to select classes or code ('unsafe reflection')","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-11-09T10:01:57.147Z","orgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","shortName":"apache"},"references":[{"tags":["vendor-advisory"],"url":"https://lists.apache.org/thread.html/hxcyk1vg9qx8bzos8g3kx91nz8d23jgt"}],"source":{"discovery":"UNKNOWN"},"title":"Apache Storm Nimbus: Submitter-Controlled Class Instantiation in Nimbus via a Fail-Open Scheduler Strategy Allowlist","x_generator":{"engine":"Vulnogram 1.0.3"}}},"cveMetadata":{"assignerOrgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","assignerShortName":"apache","cveId":"CVE-2026-82440","datePublished":"2026-11-09T10:01:57.147Z","dateReserved":"2026-08-29T10:42:00.358Z","dateUpdated":"2026-11-09T10:13:16.862Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-11-09 10:17:11","lastModifiedDate":"2026-11-09 11:17:26","problem_types":["CWE-470","CWE-470 CWE-470 Use of Externally-Controlled input to select classes or code ('unsafe reflection')"],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"82440","Ordinal":"1","Title":"Apache Storm Nimbus: Submitter-Controlled Class Instantiation in","CVE":"CVE-2026-82440","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"82440","Ordinal":"1","NoteData":"Description\n\nNimbus instantiates the class named by a topology's `topology.scheduler.strategy` when scheduling it. The\nallowlist intended to constrain that choice, `nimbus.scheduler.strategy.class.whitelist`, was treated as\n\"allow any class\" when unset, and it had no entry in the shipped `defaults.yaml`, so unset was the shipped\nstate. An authenticated submitter could therefore cause Nimbus to instantiate any class on the Nimbus\nclasspath that has a no-argument constructor.\n\nStorm's own production artifacts contain classes with side effects suitable for this: instantiating\n`org.apache.storm.testing.InProcessZookeeper` starts a ZooKeeper server with its own threads and sockets\nand nothing closes it, and `org.apache.storm.LocalCluster` behaves similarly. Repeated submissions\ntherefore consume threads, sockets and memory in the most privileged daemon in the cluster.\n\nMitigation\n\nUpgrade to 3.1.0, where an unset allowlist means the strategies shipped with Storm rather than any class.\n\nNote that this is a behaviour change: a cluster running an out-of-tree scheduler strategy without an\nexplicit allowlist will have those topologies refused until the class is added to\n`nimbus.scheduler.strategy.class.whitelist`. The rejection message names the refused class and the\nconfiguration key.\n\nUsers who cannot upgrade immediately should set `nimbus.scheduler.strategy.class.whitelist` explicitly to\nthe strategies they intend to permit.","Type":"Description","Title":"Apache Storm Nimbus: Submitter-Controlled Class Instantiation in"}]}}}