CVE-2026-82426
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk42th percentile - higher than 42% of all known CVEs
Summary
A vulnerability in Apache Storm allows an authenticated user with topology submission rights to specify any server-side path as the topology jar, bypassing the intended file upload flow. Nimbus opens the path without verifying it was uploaded, enabling access to files readable by the Nimbus daemon user.
Risk Assessment
An attacker can access sensitive data such as the Nimbus Kerberos keytab, TLS private keys, or ZooKeeper credentials. Possession of the Nimbus keytab can escalate privileges to cluster administrator, posing a critical risk to the entire environment.
Recommendation
Upgrade Apache Storm to version 3.1.0 or later, where the submitted path is canonicalized and must resolve inside the Nimbus inbox. If immediate upgrade is not possible, restrict topology submission to trusted principals via `nimbus.users` or `nimbus.groups`, and rotate the Kerberos keytab, TLS keys, and ZooKeeper credentials.
Other vulnerabilities in Apache Storm
See all- CVE-2014-0115High
Directory traversal vulnerability in the log viewer in Apache Storm 0.9.0.1 allows remote attackers to read arbitrary files via a .. (dot dot) in the file parameter to log.
- CVE-2026-82435Critical
In Apache Storm before 3.1.0, a vulnerability exists: the Netty decoder is installed before authentication and processes frames without verification, allowing an unauthenticated attacker to allocate large buffers and potentially cause memory pressure on workers.
- CVE-2026-82431Critical
In Apache Storm's SimpleACLAuthorizer, authorization returned early when nimbus.users was empty, skipping evaluation of nimbus.groups. As a result, a cluster restricted by group alone allowed every authenticated principal to perform all user-level operations, including submitTopology, beginFileUpload and getNimbusConf. The issue is fixed in version 3.1.0.
- CVE-2026-82441Critical
A vulnerability in Apache Storm allows a topology submitter to delete blobs belonging to other topologies by listing their keys in `dependency_jars` and `dependency_artifacts`. Additionally, missing validation can cause Nimbus to fail to retain leadership, rendering the cluster inoperative.
- CVE-2026-82439Critical
The DRPC server in Apache Storm keeps a map from function names to request queues, and entries are never removed. An attacker can send arbitrary function names without authentication (as `drpc.authorizer` is disabled by default), leading to unbounded memory growth and eventual heap exhaustion.
- CVE-2015-3188Critical
The UI daemon in Apache Storm 0.10.0 before 0.10.0-beta1 allows remote attackers to execute arbitrary code via unspecified vectors.
- CVE-2026-82438High
Three separate mechanisms in Apache Storm's HTTP components allowed a web page on an unrelated origin to read responses served to an authenticated user. The Logviewer reflected the request's Origin header in Access-Control-Allow-Origin while also sending Access-Control-Allow-Credentials: true, the shared CORS filter was misconfigured (a response header name was supplied where an initialisation parameter name was expected, so the container applied its own credential-allowing defaults), and the UI and Logviewer wrapped API responses in a caller-supplied JSONP callback for every GET request. In each case, a page visited by an authenticated operator can read cluster, topology and log data on their behalf.
- CVE-2026-82434Medium
When ZooKeeper authentication is configured, Storm deliberately retains storm.zookeeper.topology.auth.payload in the topology configuration, and Nimbus serves that configuration to any caller with read-only topology permissions. A user granted only topology view access receives the ZooKeeper credential, which is write-capable and allows forging or removing topology state. The credential also reaches logs (INFO in the submission client, DEBUG in SASL handlers), and version 3.1.0 removes it from the served configuration and logs.
- CVE-2026-82433Medium
In Apache Storm before 3.1.0, the getNimbusConf function returns full configuration without redaction, and the UI endpoint /api/v1/cluster/configuration lacks proper authorization, potentially exposing passwords and keys.
- CVE-2026-82432High
In Apache Storm before 3.1.0, the rebalance operation does not revalidate the blobstore map for permissions, and listBlobs lacks authorization checks, allowing an authorized user to access disallowed blobs and disclose metadata.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS