Apache Storm Prometheus Reporter: Disabling TLS verification for Prometheus Reporter also disables it for all other connections
Summary
| CVE | CVE-2026-40557 |
|---|---|
| State | PUBLISHED |
| Assigner | apache |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-04-27 14:16:48 UTC |
| Updated | 2026-05-05 18:11:10 UTC |
| Description | Improper Certificate Validation via Global SSL Context Downgrade in Apache Storm Prometheus Reporter Versions Affected: from 2.6.3 to 2.8.6 Description: In production deployments where an administrator enables storm.daemon.metrics.reporter.plugin.prometheus.skip_tls_validation (by default it is disabled) intending to affect only the Prometheus reporter, the undocumented global side effect creates an attack surface across every TLS-protected communication channel in the Storm daemon. The PrometheusPreparableReporter class implements an INSECURE_TRUST_MANAGER that accepts all SSL certificates without validation, with empty checkClientTrusted and checkServerTrusted methods. Most critically, when the storm.daemon.metrics.reporter.plugin.prometheus.skip_tls_validation configuration option is enabled (default = disabled) for HTTPS Prometheus PushGateway connections, the INSECURE_CONNECTION_FACTORY calls SSLContext.setDefault(sslContext), which globally replaces the JVM's default SSL context rather than applying the insecure context only to the Prometheus connection. This payload flows through storm.yaml configuration → PrometheusPreparableReporter.prepare() → INSECURE_CONNECTION_FACTORY → SSLContext.setDefault(), resulting in a JVM-wide TLS security downgrade. All subsequent HTTPS connections in the process - including ZooKeeper, Thrift, Netty, and UI connections - silently trust all certificates, including self-signed, expired, and attacker-generated ones, enabling man-in-the-middle interception of cluster state, topology submissions, tuple data, and administrative credentials. Mitigation: 2.x users should upgrade to 2.8.7 if the Prometheus Metrics Reporter is used. Prometheus Metrics Reporter Users who cannot upgrade immediately should remove the storm.daemon.metrics.reporter.plugin.prometheus.skip_tls_validation: true setting from their storm.yaml configuration and instead configure a proper truststore containing the PushGateway's certificate. |
Risk And Classification
Primary CVSS: v3.1 4.8 MEDIUM from ADP
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS: 0.000200000 probability, percentile 0.055700000 (date 2026-05-05)
Problem Types: CWE-295 | CWE-295 CWE-295 Improper Certificate Validation
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 4.8 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 4.8 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
LowIntegrity
LowAvailability
NoneCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Apache | Storm Prometheus Reporter | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Apache Software Foundation | Apache Storm Prometheus Reporter | affected 2.6.3 2.8.7 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.openwall.com/lists/oss-security/2026/04/25/2 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Mailing List, Third Party Advisory |
| lists.apache.org/thread/f5bv68z1y5xstz22psjk05p3wn86knjq | [email protected] | lists.apache.org | Mailing List, Vendor Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: K (en)
There are currently no legacy QID mappings associated with this CVE.