Bug 2547102 (CVE-2026-102411)

Summary: CVE-2026-102411 elasticsearch: Elasticsearch: Denial of Service via excessive memory allocation during index template retrieval
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: doconnor
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Elasticsearch. An authenticated user with index template management privileges can cause a Denial of Service (DoS) by registering multiple template resources and requesting them together. Although size limits exist for individual metadata entries, the system does not restrict cumulative memory consumption when retrieving multiple resources at once. This can exhaust available memory and cause the affected node to crash.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2558255, 2558256    
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Description OSIDB Bzimport 2026-10-06 19:52:28 UTC 
Allocation of Resources Without Limits or Throttling (CWE-770) in Elasticsearch can lead to Denial of Service via Excessive Allocation (CAPEC-130). Elasticsearch enforces a size limit on the user-supplied metadata field for each individual template resource, but does not limit the total memory used when multiple such resources are retrieved together. A user holding the *manage_index_templates* cluster privilege can register multiple resources each within the individual limit. Retrieving them together materializes all of their metadata values in memory at once, exhausting available heap and causing the affected node to fail with an out-of-memory error, resulting in a denial of service.