Description
http4k is a functional toolkit for Kotlin HTTP applications. Prior to version 5.41.0.0, there is a potential XXE (XML External Entity Injection) vulnerability when http4k handling malicious XML contents within requests, which might allow attackers to read local sensitive information on server, trigger Server-side Request Forgery and even execute code under some circumstances. Version 5.41.0.0 contains a patch for the issue.
EPSS Score:
16%
Comprehensive Technical Analysis of EUVD-2024-3444
1. Vulnerability Assessment and Severity Evaluation
The vulnerability EUVD-2024-3444, also known as CVE-2024-55875 and GHSA-7mj5-hjjj-8rgw, affects the http4k toolkit for Kotlin HTTP applications. This vulnerability is classified as an XML External Entity Injection (XXE) issue. The CVSS (Common Vulnerability Scoring System) base score of 9.8 indicates a critical severity level. The CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H breaks down as follows:
- Attack Vector (AV): Network (N) - The vulnerability is exploitable over the network.
- Attack Complexity (AC): Low (L) - The attack requires minimal skill or resources.
- Privileges Required (PR): None (N) - No special privileges are required to exploit the vulnerability.
- User Interaction (UI): None (N) - No user interaction is required for the attack to succeed.
- Scope (S): Unchanged (U) - The vulnerability does not change the security scope.
- Confidentiality (C): High (H) - The vulnerability allows for unauthorized access to sensitive information.
- Integrity (I): High (H) - The vulnerability allows for unauthorized modification of data.
- Availability (A): High (H) - The vulnerability allows for disruption of services.
2. Potential Attack Vectors and Exploitation Methods
The XXE vulnerability can be exploited by sending specially crafted XML content within HTTP requests. Potential attack vectors include:
- Reading Local Files: An attacker can craft an XML payload that includes external entities referencing local files, allowing them to read sensitive information from the server.
- Server-Side Request Forgery (SSRF): By including external entities that reference internal or external network resources, an attacker can trigger SSRF attacks, potentially accessing internal services or resources.
- Code Execution: Under certain conditions, an attacker might be able to execute arbitrary code on the server by exploiting the XXE vulnerability.
3. Affected Systems and Software Versions
The vulnerability affects all versions of http4k prior to 5.41.0.0. Organizations using http4k for Kotlin HTTP applications should immediately assess their systems to determine if they are running a vulnerable version.
4. Recommended Mitigation Strategies
To mitigate the risk associated with this vulnerability, the following steps are recommended:
- Upgrade to Version 5.41.0.0: Immediately upgrade to http4k version 5.41.0.0 or later, which includes a patch for the XXE vulnerability.
- Input Validation: Implement strict input validation for XML content to prevent the inclusion of malicious external entities.
- Disable External Entities: Configure XML parsers to disable the processing of external entities.
- Monitoring and Logging: Enhance monitoring and logging to detect and respond to any suspicious XML processing activities.
5. Impact on European Cybersecurity Landscape
The EUVD-2024-3444 vulnerability poses a significant risk to European organizations using http4k for their HTTP applications. Given the critical nature of the vulnerability, it is essential for organizations to prioritize patching and mitigation efforts to prevent potential data breaches, service disruptions, and unauthorized access. The European Union Agency for Cybersecurity (ENISA) should issue advisories and guidelines to raise awareness and provide actionable recommendations for affected entities.
6. Technical Details for Security Professionals
For security professionals, the following technical details are pertinent:
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Vulnerable Code: The vulnerability is likely present in the XML processing code within the http4k library. The specific lines of code can be reviewed in the referenced GitHub commit and file:
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Patch Details: The patch in version 5.41.0.0 likely involves disabling external entities in the XML parser configuration. Security professionals should review the patch to understand the changes and ensure similar vulnerabilities are not introduced in the future.
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References:
By following these recommendations and staying informed about the vulnerability, organizations can effectively mitigate the risks associated with EUVD-2024-3444.