CVE-2018-17247: Elasticsearch Improper Restriction Of XML External Vulnerability

MODERATE
Advisory Identifier: GHSA-ccmr-qj26-845g
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CVSS 5.9
CWE-611
Published
Advisory Summary

CVE-2018-17247 is a MODERATE (CVSS 5.9) improper restriction of xml external vulnerability (CWE-611: Improper Restriction of XML External Entity Reference) affecting Elasticsearch libraries in the Maven ecosystem. The issue involves improper restriction of xml external entity reference in elasticsearch. Remediation is available by upgrading affected packages to version 6.5.2.

CVE-2018-17247 at a Glance

CVE Identifier CVE-2018-17247
GHSA Identifier GHSA-ccmr-qj26-845g
Severity MODERATE
CVSS v3.1 Base Score 5.9
CWE Classification CWE-611: Improper Restriction of XML External Entity Reference
Affected Product Elasticsearch
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 5.9

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2018-17247

To remediate this vulnerability, upgrade all affected Elasticsearch dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

org.elasticsearch:elasticsearch fixed: 6.5.2 
<dependency>
    <groupId>org.elasticsearch</groupId>
    <artifactId>elasticsearch</artifactId>
    <version>6.5.2</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree -Dincludes=org.elasticsearch

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2018-17247, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.elasticsearch

Analyze the terminal output to locate any version of Elasticsearch in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 6.5.2), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.elasticsearch command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-611: Improper Restriction of XML External Entity Reference, where the product processes an xml document that can contain xml entities with uris that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output. In Elasticsearch, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

Elasticsearch Security versions 6.5.0 and 6.5.1 contain an XXE flaw in Machine Learning's find_file_structure API. If a policy allowing external network access has been added to Elasticsearch's Java Security Manager then an attacker could send a specially crafted request capable of leaking content of local files on the Elasticsearch node. This could allow a user to access information that they should not have access to.

CVE-2018-17247 Affected Elasticsearch Versions

1 component(s)
Fixed Versions:
6.5.2
Product / Package Ecosystem Affected Versions Fixed Version
org.elasticsearch:elasticsearch
maven/org.elasticsearch/elasticsearch
Maven
≥ 6.5.0
< 6.5.2
6.5.2

References

NVD — CVE-2018-17247 NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-17247
Elasticsearch Security Information SECURITY
https://discuss.elastic.co/t/elastic-stack-6-5-2-security-update/159594
Elasticsearch Security Information SECURITY
https://www.elastic.co/community/security
Elasticsearch Security Information SECURITY
http://www.securityfocus.com/bid/106294

Frequently Asked Questions

What is CVE-2018-17247?
CVE-2018-17247 is a security vulnerability in Elasticsearch involving Improper Restriction of XML External Entity Reference in Elasticsearch under CWE-611: Improper Restriction of XML External Entity Reference.
Which Elasticsearch versions are affected?
Affected versions include releases prior to 6.5.2 across affected packages: org.elasticsearch:elasticsearch.
What version fixes CVE-2018-17247?
Upgrading to 6.5.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is elasticsearch affected?
Yes, org.elasticsearch:elasticsearch is affected in releases prior to 6.5.2. Upgrade your dependency to 6.5.2 or later.
What is the CVSS score of CVE-2018-17247?
CVE-2018-17247 has a CVSS v3.1 base score of 5.9 (MODERATE) with vector string CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2018-17247?
CVE-2018-17247 is classified under CWE-611: Improper Restriction of XML External Entity Reference (The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.).
How can I check Maven dependencies for CVE-2018-17247?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.elasticsearch'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-ccmr-qj26-845g",
  "modified" : "2022-06-28T23:22:46Z",
  "published" : "2022-05-13T01:34:04Z",
  "aliases" : [ "CVE-2018-17247" ],
  "summary" : "Improper Restriction of XML External Entity Reference in Elasticsearch",
  "details" : "Elasticsearch Security versions 6.5.0 and 6.5.1 contain an XXE flaw in Machine Learning's find_file_structure API. If a policy allowing external network access has been added to Elasticsearch's Java Security Manager then an attacker could send a specially crafted request capable of leaking content of local files on the Elasticsearch node. This could allow a user to access information that they should not have access to.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.elasticsearch:elasticsearch"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "6.5.0"
      }, {
        "fixed" : "6.5.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2018-17247"
  }, {
    "type" : "WEB",
    "url" : "https://discuss.elastic.co/t/elastic-stack-6-5-2-security-update/159594"
  }, {
    "type" : "WEB",
    "url" : "https://www.elastic.co/community/security"
  }, {
    "type" : "WEB",
    "url" : "http://www.securityfocus.com/bid/106294"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-611" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2022-06-28T23:22:46Z",
    "nvd_published_at" : "2018-12-20T22:29:00Z"
  }
}