CVE-2026-41081 | Apache Storm Client: Anonymous principal assigned on TLS client certificate verification failure

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

Published: 2026-04-27 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-41081 is rated Low Risk (33.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.29%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-41081

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.09% 0.29% +0.19%
2 2026-04-29 0.04% 0.09% +0.06%
3 2026-04-28 0.04%

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-41081

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 2.5 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-41081

GitHub Security Advisory for CVE-2026-41081

GHSA-j2q8-xx3q-8fqh · Severity: medium · Ecosystem: maven — Apache Storm's Improper Handling of TLS Client Authentication Failure Leads to Anonymous Principal Assignment

Affected software / configurations for CVE-2026-41081

Vendor Product Version Raw CPE
apache storm < 2.8.7 cpe:2.3:a:apache:storm:*:*:*:*:*:*:*:*

References for CVE-2026-41081

cvelogic Threat Intelligence