CVE-2021-22134 : Exploit Details and Defense Strategies
Learn about CVE-2021-22134 affecting Elasticsearch versions after 7.6.0 and before 7.11.0. Understand the impact, technical details, and mitigation steps to secure your Elasticsearch environment.
A document disclosure flaw was found in Elasticsearch versions after 7.6.0 and before 7.11.0, potentially exposing sensitive data to unauthorized users.
Understanding CVE-2021-22134
This CVE discloses a vulnerability in Elasticsearch versions that could allow attackers to view documents and fields they are not authorized to access.
What is CVE-2021-22134?
A flaw in Elasticsearch versions after 7.6.0 and before 7.11.0 results in improper application of security permissions during query execution, potentially revealing restricted content.
The Impact of CVE-2021-22134
This vulnerability could lead to unauthorized users accessing sensitive information by disclosing the existence of documents and fields they should not be able to view.
Technical Details of CVE-2021-22134
The technical details include the vulnerability description, affected systems, and the exploitation mechanism.
Vulnerability Description
The vulnerability arises due to the failure of Get requests to enforce security permissions correctly, especially when querying updated documents not yet refreshed in the index.
Affected Systems and Versions
Elasticsearch versions after 7.6.0 and before 7.11.0 are impacted by this vulnerability when Document or Field Level Security is implemented.
Exploitation Mechanism
Attackers can exploit this flaw by executing queries against recently updated documents, potentially retrieving sensitive data.
Mitigation and Prevention
To address CVE-2021-22134, immediate steps must be taken, and long-term security practices should be adopted along with timely patching and updates.
Immediate Steps to Take
Users are advised to update their Elasticsearch instances to versions beyond 7.11.0 and refresh indices containing updated documents to mitigate the risk.
Long-Term Security Practices
Implement strict access controls, regularly refresh indices, and monitor Elasticsearch activity for any unauthorized access attempts.
Patching and Updates
Regularly apply security patches and updates provided by Elastic to ensure protection against known vulnerabilities.