CVE-2021-37939 is a low-severity vulnerability affecting Elastic's Kibana, specifically its JIRA connector and IBM Resilient connector. This vulnerability allows malicious users with permission to create connectors to potentially access HTTP response data from internal hosts that are otherwise hidden from public view. The attack vector is network-based, and it requires high privileges to exploit.
The CVSS score of this vulnerability is 2.7, indicating a low severity level. Organizations should understand that while the risk is deemed low, any unauthorized access to internal resources poses a risk to confidentiality. Therefore, it is crucial for organizations to assess their exposure and take appropriate action.
Exploitation status indicates that this vulnerability is not actively exploited in the wild, and no public proof of concept (PoC) exists. However, the potential for unauthorized access means that organizations should prioritize patching as part of their security posture.
Organizations should prioritize patching immediately. The vulnerability was published on November 18, 2021, and has since been modified, emphasizing the need for vigilance in monitoring security updates.
Vulnerability Details
The vulnerability allows the Kibana JIRA connector and the IBM Resilient connector to return HTTP response data on internal hosts. This behavior may expose sensitive information that is not intended for external visibility. The vulnerability is classified under CWE-200 (Information Exposure) and CWE-319 (Improper Restriction of Operations within the Bounds of a Memory Buffer).
The CVSS score of 2.7 indicates that the vulnerability has a low severity level, which means that while it poses a risk, it may not be the highest priority for immediate remediation compared to more severe vulnerabilities. However, the potential for information exposure should not be underestimated.
Affected versions of Kibana include all versions from 7.8.0 to 7.15.2, as outlined in the vendor's advisory. Organizations utilizing these versions should take steps to upgrade to a patched version as soon as possible.
Technical Analysis
The root cause of this vulnerability lies in the improper handling of internal HTTP responses by Kibana's connectors. The attack vector is network-based, and the complexity is low, making exploitation relatively straightforward for an attacker with the appropriate privileges.
To exploit this vulnerability, the attacker must have high privileges, which limits the risk to those users who can create connectors. There is no user interaction required, which means that an attacker can perform this action without needing to trick users into engaging.
The impact on confidentiality is low since the data exposed is limited HTTP response data, with no integrity or availability impacts recorded. Organizations must ensure that their configurations limit exposure to such vulnerabilities.
Risk & Impact Analysis
Risk to organizations includes unauthorized access to sensitive internal information, which can lead to further exploitation or data breaches. Although the severity is classified as low, the potential for exploitation should not be dismissed, as attackers often look for ways to leverage any access they can gain.
The blast radius for this vulnerability is relatively contained, limited to the internal network and users with connector creation privileges. However, organizations must assess the security configurations of their Kibana installations to ensure that such vulnerabilities are mitigated effectively.
Given the low CVSS score, organizations should schedule remediation during their next patch cycle. Monitoring for unusual behavior related to connector activity may also help in identifying potential exploitation attempts.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | No |
Public PoC | No |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The specific versions of Kibana affected by this vulnerability are those between 7.8.0 and 7.15.2. Organizations should ensure they are running a version of Kibana that is patched against this vulnerability.
Mitigation & Remediation
Organizations should prioritize applying patches or updates to Kibana to remediate this vulnerability. The recommended action is to upgrade to a version higher than 7.15.2, where this vulnerability is resolved. Additionally, organizations can implement network segmentation and restrict permissions on connector creation to mitigate potential exploitation.
For further guidance on security testing and vulnerability management, organizations can refer to resources such as penetration testing services.
Detection Guidance
To detect potential exploitation attempts of this vulnerability, organizations should monitor logs for unusual connector creation activities and HTTP response data access patterns. Behavioral anomalies indicating unauthorized access to internal resources should also be flagged for review.
AppSecure Threat Intelligence Insight
The long-term significance of CVE-2021-37939 lies in its illustration of how misconfigured connectors can lead to information exposure. This vulnerability serves as a reminder for organizations to regularly audit their security configurations and implement best practices for managing access controls.
Security teams should learn from this incident and ensure that all systems, especially those interfacing with internal services, have stringent access controls. To bolster their defenses, organizations may consider adopting a comprehensive vulnerability management program to address similar weaknesses in the future.
For strategic defensive takeaways, organizations are encouraged to regularly update their software and stay informed about emerging vulnerabilities. The importance of a robust incident response plan cannot be overstated, as it prepares teams to act swiftly in the event of a security breach.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
.webp)