CVE-2026-40557Apache Storm Prometheus Reporter: Disabling TLS verification for Prometheus Reporter also disables it for all other connections
- 4.8MediumCVSS base score
- 0.19%Exploitation in 30 daysEPSS · top 91% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By apache
- 13 days later
· 13 days later
Published
- 3 days later
· 3 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Medium4.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N |
| NVDNVD · Analyzed | 3.1 | Medium4.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.19% · top 91% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.8.
Affected products
Apache Software Foundation · Apache Storm Prometheus Reporter
- affected 2.6.3 – < 2.8.7
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Mavenorg.apache.storm:storm-metrics-prometheusGHSA-82fm-wpc2-5pmp (opens in a new tab)
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-25846 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-82fm-wpc2-5pmp (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-40557)Record last updated .