Vulnerability-Lookup

FKIE_CVE-2026-82426

Vulnerability from fkie_nvd - Published: 2026-09-14 15:17 - Updated: 2026-09-14 20:58

Severity

6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Summary

Description Nimbus accepted the `uploadedJarLocation` argument of `submitTopology` / `submitTopologyWithOpts` as a server-side path and opened it directly, without checking that it referred to a file the caller had actually uploaded. The intended flow is that a client first calls `beginFileUpload`, which returns a path inside the Nimbus inbox, and uploads the jar in chunks to that location; nothing bound submission to that flow, and the `uploaders` map populated by `beginFileUpload` was never consulted at submit time. An authenticated user with topology submission rights could therefore submit any path readable by the Nimbus daemon user as their topology jar. Nimbus copied the file into the topology's jar blob, and the blob ACL grants the submitting subject read access, so the contents could then be retrieved with the ordinary blob download RPCs. Candidate targets include the Nimbus Kerberos keytab, Thrift and UI TLS private keys, and `storm.yaml` with the ZooKeeper authentication payload. Possession of the Nimbus keytab turns an ordinary tenant into a cluster administrator. In a deployment configured as the documentation recommends, submission is available to every authenticated principal when `nimbus.users` is unset, so no elevated privilege is required. Mitigation Upgrade to 3.1.0, where the submitted location is canonicalised and must resolve inside the Nimbus inbox. Users who cannot upgrade immediately should restrict topology submission to trusted principals via `nimbus.users` or `nimbus.groups`, and should treat any file readable by the Nimbus daemon user as potentially exposed to submitters: rotate the Nimbus keytab and any TLS private keys or ZooKeeper credentials reachable from that account. Local mode is unaffected. Credit Independently reported to the Apache Storm PMC by n0mi1k, with a proof of concept. Also found by the ASF using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.

References

	URL	Tags
	security@apache.org	https://lists.apache.org/thread/cq3xzxvvhtb6brbp9nl9p8kobnvtmnwc
	af854a3a-2127-422b-91ae-364da2661108	http://www.openwall.com/lists/oss-security/2026/09/13/6

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://repo.maven.apache.org/maven2/",
          "defaultStatus": "unaffected",
          "packageName": "org.apache.storm:storm-server",
          "product": "Apache Storm Nimbus",
          "vendor": "Apache Software Foundation",
          "versions": [
            {
              "lessThan": "3.1.0",
              "status": "affected",
              "version": "3.0.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "security@apache.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Description\n\nNimbus accepted the `uploadedJarLocation` argument of `submitTopology` / `submitTopologyWithOpts` as a\nserver-side path and opened it directly, without checking that it referred to a file the caller had\nactually uploaded. The intended flow is that a client first calls `beginFileUpload`, which returns a path\ninside the Nimbus inbox, and uploads the jar in chunks to that location; nothing bound submission to that\nflow, and the `uploaders` map populated by `beginFileUpload` was never consulted at submit time.\n\nAn authenticated user with topology submission rights could therefore submit any path readable by the\nNimbus daemon user as their topology jar. Nimbus copied the file into the topology\u0027s jar blob, and the\nblob ACL grants the submitting subject read access, so the contents could then be retrieved with the\nordinary blob download RPCs. Candidate targets include the Nimbus Kerberos keytab, Thrift and UI TLS\nprivate keys, and `storm.yaml` with the ZooKeeper authentication payload. Possession of the Nimbus keytab\nturns an ordinary tenant into a cluster administrator.\n\nIn a deployment configured as the documentation recommends, submission is available to every\nauthenticated principal when `nimbus.users` is unset, so no elevated privilege is required.\n\nMitigation\n\nUpgrade to 3.1.0, where the submitted location is canonicalised and must resolve inside the Nimbus inbox.\n\nUsers who cannot upgrade immediately should restrict topology submission to trusted principals via\n`nimbus.users` or `nimbus.groups`, and should treat any file readable by the Nimbus daemon user as\npotentially exposed to submitters: rotate the Nimbus keytab and any TLS private keys or ZooKeeper\ncredentials reachable from that account. Local mode is unaffected.\n\n\nCredit\n\nIndependently reported to the Apache Storm PMC by n0mi1k, with a proof of concept.\n\nAlso found by the ASF using Claude agents to study the security of open-source projects, validated and reported by Apache Storm."
    }
  ],
  "id": "CVE-2026-82426",
  "lastModified": "2026-09-14T20:58:48.430",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-82426",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-14T19:53:24.403566Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-14T15:17:09.410",
  "references": [
    {
      "source": "security@apache.org",
      "url": "https://lists.apache.org/thread/cq3xzxvvhtb6brbp9nl9p8kobnvtmnwc"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "http://www.openwall.com/lists/oss-security/2026/09/13/6"
    }
  ],
  "sourceIdentifier": "security@apache.org",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-22"
        }
      ],
      "source": "security@apache.org",
      "type": "Secondary"
    }
  ]
}

CVE-2026-82426 (GCVE-0-2026-82426)

Vulnerability from cvelistv5 – Published: 2026-09-14 14:04 – Updated: 2026-09-14 19:53

Title

Apache Storm Nimbus: Arbitrary File Read on Nimbus via Unvalidated Uploaded Jar Location

Summary

Severity

6.5 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-14 19:53 UTC

CWE

CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Assigner

apache mitre root

References

2 references

URL	Tags
https://lists.apache.org/thread/cq3xzxvvhtb6brbp9…	vendor-advisory
http://www.openwall.com/lists/oss-security/2026/09/13/6

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache Storm Nimbus	Affected: 3.0.0 , < 3.1.0 (semver)

Credits

n0mi1k The ASF using Claude Agents

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2026-09-14T14:13:17.028Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/09/13/6"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 6.5,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-82426",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-14T19:53:24.403566Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-14T19:53:45.290Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://repo.maven.apache.org/maven2/",
          "defaultStatus": "unaffected",
          "packageName": "org.apache.storm:storm-server",
          "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": "n0mi1k"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "The ASF using Claude Agents"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cb\u003eDescription\u003c/b\u003e\u003cbr\u003e\u003cbr\u003eNimbus accepted the `uploadedJarLocation` argument of `submitTopology` / `submitTopologyWithOpts` as a\u003cbr\u003eserver-side path and opened it directly, without checking that it referred to a file the caller had\u003cbr\u003eactually uploaded. The intended flow is that a client first calls `beginFileUpload`, which returns a path\u003cbr\u003einside the Nimbus inbox, and uploads the jar in chunks to that location; nothing bound submission to that\u003cbr\u003eflow, and the `uploaders` map populated by `beginFileUpload` was never consulted at submit time.\u003cbr\u003e\u003cbr\u003eAn authenticated user with topology submission rights could therefore submit any path readable by the\u003cbr\u003eNimbus daemon user as their topology jar. Nimbus copied the file into the topology\u0027s jar blob, and the\u003cbr\u003eblob ACL grants the submitting subject read access, so the contents could then be retrieved with the\u003cbr\u003eordinary blob download RPCs. Candidate targets include the Nimbus Kerberos keytab, Thrift and UI TLS\u003cbr\u003eprivate keys, and `storm.yaml` with the ZooKeeper authentication payload. Possession of the Nimbus keytab\u003cbr\u003eturns an ordinary tenant into a cluster administrator.\u003cbr\u003e\u003cbr\u003eIn a deployment configured as the documentation recommends, submission is available to every\u003cbr\u003eauthenticated principal when `nimbus.users` is unset, so no elevated privilege is required.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eMitigation\u003c/b\u003e\u003cbr\u003e\u003cbr\u003eUpgrade to 3.1.0, where the submitted location is canonicalised and must resolve inside the Nimbus inbox.\u003cbr\u003e\u003cbr\u003eUsers who cannot upgrade immediately should restrict topology submission to trusted principals via\u003cbr\u003e`nimbus.users` or `nimbus.groups`, and should treat any file readable by the Nimbus daemon user as\u003cbr\u003epotentially exposed to submitters: rotate the Nimbus keytab and any TLS private keys or ZooKeeper\u003cbr\u003ecredentials reachable from that account. Local mode is unaffected.\u003cdiv\u003e\u003cbr\u003e\u003c/div\u003e\u003cdiv\u003e\u003cb\u003eCredit\u003c/b\u003e\u003cbr\u003e\u003cbr\u003eIndependently reported to the Apache Storm PMC by n0mi1k, with a proof of concept.\u003cbr\u003e\u003cbr\u003eAlso found by the ASF using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.\u003c/div\u003e"
            }
          ],
          "value": "Description\n\nNimbus accepted the `uploadedJarLocation` argument of `submitTopology` / `submitTopologyWithOpts` as a\nserver-side path and opened it directly, without checking that it referred to a file the caller had\nactually uploaded. The intended flow is that a client first calls `beginFileUpload`, which returns a path\ninside the Nimbus inbox, and uploads the jar in chunks to that location; nothing bound submission to that\nflow, and the `uploaders` map populated by `beginFileUpload` was never consulted at submit time.\n\nAn authenticated user with topology submission rights could therefore submit any path readable by the\nNimbus daemon user as their topology jar. Nimbus copied the file into the topology\u0027s jar blob, and the\nblob ACL grants the submitting subject read access, so the contents could then be retrieved with the\nordinary blob download RPCs. Candidate targets include the Nimbus Kerberos keytab, Thrift and UI TLS\nprivate keys, and `storm.yaml` with the ZooKeeper authentication payload. Possession of the Nimbus keytab\nturns an ordinary tenant into a cluster administrator.\n\nIn a deployment configured as the documentation recommends, submission is available to every\nauthenticated principal when `nimbus.users` is unset, so no elevated privilege is required.\n\nMitigation\n\nUpgrade to 3.1.0, where the submitted location is canonicalised and must resolve inside the Nimbus inbox.\n\nUsers who cannot upgrade immediately should restrict topology submission to trusted principals via\n`nimbus.users` or `nimbus.groups`, and should treat any file readable by the Nimbus daemon user as\npotentially exposed to submitters: rotate the Nimbus keytab and any TLS private keys or ZooKeeper\ncredentials reachable from that account. Local mode is unaffected.\n\n\nCredit\n\nIndependently reported to the Apache Storm PMC by n0mi1k, with a proof of concept.\n\nAlso found by the ASF using Claude agents to study the security of open-source projects, validated and reported by Apache Storm."
        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
              "text": "important"
            },
            "type": "Textual description of severity"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-22",
              "description": "CWE-22 Improper Limitation of a Pathname to a Restricted Directory (\u0027Path Traversal\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-14T14:04:16.954Z",
        "orgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
        "shortName": "apache"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://lists.apache.org/thread/cq3xzxvvhtb6brbp9nl9p8kobnvtmnwc"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Apache Storm Nimbus: Arbitrary File Read on Nimbus via Unvalidated Uploaded Jar Location",
      "x_generator": {
        "engine": "Vulnogram 1.0.3"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
    "assignerShortName": "apache",
    "cveId": "CVE-2026-82426",
    "datePublished": "2026-09-14T14:04:16.954Z",
    "dateReserved": "2026-08-29T10:01:40.256Z",
    "dateUpdated": "2026-09-14T19:53:45.290Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.