It was reported that Elasticsearch versions 1.3.0-1.3.7 and 1.4.0-1.4.2 have vulnerabilities in the Groovy scripting engine. The vulnerability allows an attacker to construct Groovy scripts that escape the sandbox and execute shell commands as the user running the Elasticsearch Java VM.

Upstream bug report: https://github.com/elasticsearch/elasticsearch/issues/9655

Upstream fixes: 1.3: https://github.com/elasticsearch/elasticsearch/commit/69735b0f4ab9ad7df4b82e8c917589b52cb9978c 1.4: https://github.com/elasticsearch/elasticsearch/commit/4e952b2d75de6ca4caf4b6743462714f3b60d07f 1.x: https://github.com/elasticsearch/elasticsearch/commit/716f0b24dc5414616e8dc0590dbfcfa0081be892

Mitigation: Users can address the vulnerability by setting script.groovy.sandbox.enabled to false in config/elasticsearch.yml and restarting the node.

Common Vulnerabilities and Exposures assigned an identifier CVE-2014-3120 to the following vulnerability:

Name: CVE-2014-3120 URL: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-3120 Assigned: 20140429 Reference: EXPLOIT-DB:33370 Reference: http://www.exploit-db.com/exploits/33370 Reference: http://bouk.co/blog/elasticsearch-rce/ Reference: http://www.rapid7.com/db/modules/exploit/multi/elasticsearch/scriptmvelrce Reference: https://www.found.no/foundation/elasticsearch-security/#staying-safe-while-developing-with-elasticsearch Reference: http://www.securityfocus.com/bid/67731 Reference: OSVDB:106949 Reference: http://www.osvdb.org/106949

The default configuration in Elasticsearch before 1.2 enables dynamic scripting, which allows remote attackers to execute arbitrary MVEL expressions and Java code via the source parameter to search. NOTE: this only violates the vendor's intended security policy if the user does not run Elasticsearch in its own independent virtual machine.

As noted in <http://bouk.co/blog/elasticsearch-rce/>, adding "script.disabledynamic: true" to elasticsearch.yml, and ensuring Elasticsearch only binds to localhost, can help mitigate this issue.

Uncontrolled Resource Consumption (CWE-400) in Elasticsearch can lead to denial of service via Excessive Allocation (CAPEC-130). A low-privileged authenticated user with permission to execute EQL sequence queries against an index they control can send a specially crafted query that triggers excessive memory consumption, causing the Elasticsearch node to crash.

Incorrect Authorization (CWE-863) in Elasticsearch can allow an authenticated user with limited index privileges to exploit insufficient authorization controls in the ingest simulation feature. By targeting indices they are not authorized to access directly, the user can cause those indices' configured ingest pipelines to execute and return their output, potentially disclosing data processed or enriched by those pipelines. Additionally, the same feature can be used to retrieve index mapping metadata for indices the user are not authorized to access directly.

Uncontrolled Recursion (CWE-674) in Elasticsearch can lead to denial of service via a specially crafted search request submitted by a low-privileged authenticated user. A user with read-level index access can submit a request that triggers unbounded recursive processing within the Elasticsearch query evaluation component, causing a fatal error that terminates the affected node. In single-node deployments, this results in complete service outage; in multi-node clusters, it causes repeated node restarts and sustained availability degradation.

Uncontrolled Recursion (CWE-674) in Elasticsearch can lead to denial of service via Input Data Manipulation (CAPEC-153). An authenticated user holding only low-privileged index creation permissions can submit a single request containing a specially crafted, malformed custom analysis definition that is resolved recursively without a cycle or depth check, exhausting the thread stack and terminating the affected node.

Memory Allocation with Excessive Size Value (CWE-789) in Elasticsearch can lead to denial of service via Excessive Allocation (CAPEC-130). An authenticated user holding only read privileges on a single index can submit one small, specially crafted search request that causes an excessively large memory allocation, exhausting the JVM heap and terminating the affected node.

Uncontrolled Recursion (CWE-674) in Elasticsearch can lead to denial of service via Serialized Data with Nested Payloads (CAPEC-230). An authenticated user holding only read privileges on a single index can submit one specially crafted search request whose deeply nested structure is processed without a depth limit, exhausting the thread stack and terminating the affected node.

Memory Allocation with Excessive Size Value (CWE-789) in the ES|QL query processing of Elasticsearch can lead to denial of service via Excessive Allocation (CAPEC-130). An authenticated user able to submit ES|QL queries could send a specially crafted query whose evaluation allocates an unbounded amount of heap memory, exhausting the available heap on the receiving node and causing the node to become unavailable.

A flaw in Elasticsearch allows a low-privileged authenticated user to submit a single small request containing a forged opaque identifier. Elasticsearch decodes and deserializes the identifier before confirming that it was legitimately issued by the cluster, and a size value carried inside the identifier drives an allocation that is neither capped nor accounted for by the available memory-usage controls. The resulting out-of-memory condition is fatal and terminates the affected node process, resulting in a denial of service.

A flaw in Elasticsearch allows a low-privileged authenticated user to submit a single request containing a crafted user-supplied input. A specific internal component validates the input using a recursive routine and applies no bound to the length of the value being validated, so the validation causes the thread to exhaust its stack. The resulting fatal error is not handled by the surrounding execution paths and terminates the affected node process, producing a denial of service.

Allocation of Resources Without Limits or Throttling (CWE-770) in Elasticsearch can lead to a denial of service via Excessive Allocation (CAPEC-130). A user with elevated privileges can submit a specially crafted machine learning request that causes excessive memory consumption, which may render the affected node unavailable.

A flaw in Elasticsearch allows a low-privileged authenticated user who can index documents to submit a single small document containing a crafted user-supplied input. Processing one such document occupies a worker thread from a bounded pool for a disproportionate amount of time, degrading the availability of indexing operations on the affected node.