Elasticsearch impersonation via missing TLS certificate validation
Published Sep 17, 2025 · Updated Sep 17, 2025
Improper certificate validation in CISA Thorium before 1.1.2 allows remote attackers to impersonate the Elasticsearch service. The elastic connection builder previously created its transport without applying a certificate-validation policy, so it accepted an attacker-controlled TLS endpoint. The attacker must control the cluster's adjacent network path and can read or alter data exchanged with Elasticsearch, without directly interrupting service.
Summary
What happened
Improper certificate validation in CISA Thorium before 1.1.2 allows remote attackers to impersonate the Elasticsearch service. The elastic connection builder previously created its transport without applying a certificate-validation policy, so it accepted an attacker-controlled TLS endpoint. The attacker must control the cluster's adjacent network path and can read or alter data exchanged with Elasticsearch, without directly interrupting service.
The record
- CVE
- CVE-2025-35434
- Published
- Sep 17, 2025
- Updated
- Sep 17, 2025
- Vendor
- Cybersecurity and Infrastructure Security Agency (CISA)
- Product
- Thorium
- Classifications
- CWE-295, T1557
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 17, 2025CVE publishedPublication date reported by the CVE source.
- Sep 17, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=1.0.0 <1.1.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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