Evidence used
- No CISA KEV confirmation is currently recorded.
- EPSS is 0.35% for the current model date.
BlackTreeCVE IntelligenceElastic · Kibana
High technical severity; prioritise exposed affected systems while verifying vendor guidance.
High technical severity; prioritise exposed affected systems while verifying vendor guidance.
Patch availableObservable Discrepancy (CWE-203) in Kibana Fleet can lead to information disclosure via Excavation (CAPEC-116). Fleet removes the Elasticsearch API key value of an enrolled Elastic Agent from the responses of its agent listing capability, but that capability accepted caller-supplied filter expressions over the stored field that holds the value, and evaluated them with Kibana's own internal Elasticsearch privileges rather than the caller's. Because the number of matching agents is reported back to the caller, the difference between a matching and a non-matching filter formed a side channel from which the full API key value could be reconstructed one character at a time with a short sequence of requests.
Observable Discrepancy (CWE-203) in Kibana Fleet can lead to information disclosure via Excavation (CAPEC-116). Fleet removes the Elasticsearch API key value of an enrolled Elastic Agent from the responses of its agent listing capability, but that capability accepted caller-supplied filter expressions over the stored field that holds the value, and evaluated them with Kibana's own internal Elasticsearch privileges rather than the caller's. Because the number of matching agents is reported back to the caller, the difference between a matching and a non-matching filter formed a side channel from which the full API key value could be reconstructed one character at a time with a short sequence of requests.
The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may obtain information outside the intended access boundary.
Observable Discrepancy (CWE-203) in Kibana Fleet can lead to information disclosure via Excavation (CAPEC-116). Fleet removes the Elasticsearch API key value of an enrolled Elastic Agent from the responses of its agent listing capability, but that capability accepted caller-supplied filter expressions over the stored field that holds the value, and evaluated them with Kibana's own internal Elasticsearch privileges rather than the caller's. Because the number of matching agents is reported back to the caller, the difference between a matching and a non-matching filter formed a side channel from which the full API key value could be reconstructed one character at a time with a short sequence of requests.
The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may obtain information outside the intended access boundary.
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
CWE-203: Observable Discrepancy. The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:NCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
Operational remediation based on structured source evidence.
Published 13 Aug 2026 · Last source change 13 Aug 2026, 20:27 UTC · CWE-203 · Observable Discrepancy
Core structured fields are present and their contributing authorities are shown above.