CVE-2026-41081
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk21th percentile - higher than 21% of all known CVEs
Summary
Apache Storm up to 2.8.7, when TLS is enabled without requiring client certificate authentication, assigns a fallback principal CN=ANONYMOUS if no certificate is presented or verification fails. The SSLPeerUnverifiedException is caught and suppressed rather than rejecting the connection, resulting in fail-open behavior.
Risk Assessment
An unauthenticated client may obtain a principal identity and potentially bypass authorization if ACL rules do not explicitly deny access to CN=ANONYMOUS.
Recommendation
Upgrade to version 2.8.7, which handles TLS authentication failures in a fail-closed manner. If immediate upgrade is not possible, enable mandatory client certificate authentication and deny access to CN=ANONYMOUS.
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)
Improper Handling of TLS Client Authentication Failure Leading to Anonymous Principal Assignment in Apache Storm Versions Affected: up to 2.8.7 Description: When TLS transport is enabled in Apache Storm without requiring client certificate authentication (the default configuration), the TlsTransportPlugin assigns a fallback principal (CN=ANONYMOUS) if no client certificate is presented or if certificate verification fails. The underlying SSLPeerUnverifiedException is caught and suppressed rather than rejecting the connection. This fail-open behavior means an unauthenticated client can establish a TLS connection and receive a valid principal identity. If the configured authorizer (e.g., SimpleACLAuthorizer) does not explicitly deny access to CN=ANONYMOUS, this may result in unauthorized access to Storm services. The condition is logged at debug level only, reducing visibility in production. Impact: Unauthenticated clients may be assigned a principal identity, potentially bypassing authorization in permissive or misconfigured environments. Mitigation: Users should upgrade to 2.8.7 in which TLS authentication failures are handled in a fail-closed manner. Users who cannot upgrade immediately should: - Enable mandatory client certificate authentication (nimbus.thrift.tls.client.auth.required: true) - Ensure authorization rules explicitly deny access to CN=ANONYMOUS - Review all ACL configurations for implicit default-allow behavior
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

