CVE-2026-41081: Apache Storm Client · Improper Authentication
Affects Apache Storm ClientSource CVE Database V5
Not known to be exploited · CVSS 6.5 Medium : upgrade to 2.8.7 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 21% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2.8.7
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 27 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade Apache Storm Client and Apache Software Foundation/org.apache.storm:storm-client and org.apache.storm/storm-client to 2.8.7.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Apache Software FoundationApache Storm Client | Affected
| Fixed in
|
MavenApache Software Foundation/org.apache.storm:storm-clientpkg:maven/Apache Software Foundation/org.apache.storm:storm-clientOther threats | Affected
| Fixed in
|
Mavenorg.apache.storm/storm-clientpkg:maven/org.apache.storm/storm-clientOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available in Apache Storm version 2.8.7, which handles TLS authentication failures in a fail-closed manner. Users should upgrade to this version to fully remediate the issue. For those unable to upgrade immediately, it is recommended to enable mandatory client certificate authentication by setting nimbus.thrift.tls.client.auth.required to true, explicitly deny access to the CN=ANONYMOUS principal in authorization rules, and review all ACL configurations to avoid implicit default-allow permissions. These steps help mitigate unauthorized access risks until the official fix is applied.
Description
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