CVE-2015-5206 in Traffic Server
Summary
by MITRE
Unspecified vulnerability in the HTTP/2 experimental feature in Apache Traffic Server before 5.3.x before 5.3.2 has unknown impact and attack vectors, a different vulnerability than CVE-2015-5168.
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Analysis
by VulDB Data Team • 11/15/2019
The vulnerability identified as CVE-2015-5206 affects Apache Traffic Server's experimental HTTP/2 feature implementation prior to version 5.3.2. This issue represents a security flaw within the proxy server software that implements the HTTP/2 protocol standard, which was still in experimental phase at the time of discovery. The vulnerability exists specifically within the HTTP/2 experimental functionality and does not affect the standard HTTP/1.1 implementation or other protocol features of the software. The unspecified nature of the impact and attack vectors indicates that the exact technical details of how the vulnerability could be exploited were not fully disclosed in the initial CVE description, suggesting either a complex exploitation scenario or that the vulnerability was still under investigation by security researchers. This particular vulnerability is distinct from CVE-2015-5168, which indicates that multiple security issues existed within the HTTP/2 implementation of the software, each requiring separate remediation approaches.
The technical flaw within Apache Traffic Server's HTTP/2 implementation likely stems from improper handling of protocol messages, connection management, or state transitions within the experimental feature. HTTP/2 introduces complex mechanisms including multiplexed streams, header compression, and flow control that require careful implementation to prevent security issues. Given that this is an experimental feature, the implementation may have contained race conditions, buffer overflows, or improper input validation that could allow attackers to manipulate the server behavior or potentially execute arbitrary code. The experimental nature of the feature suggests that thorough security testing may not have been completed before its inclusion in the software release, leaving potential attack surfaces unaddressed. The vulnerability could manifest through malformed HTTP/2 frames, improper stream handling, or incorrect state management during protocol negotiation and data transfer operations.
The operational impact of this vulnerability could be significant for organizations relying on Apache Traffic Server's HTTP/2 functionality, particularly those operating in environments where security is paramount. Attackers exploiting this vulnerability could potentially cause denial of service conditions, unauthorized access to server resources, or even complete system compromise depending on the specific nature of the flaw. The experimental status of the feature means that organizations may have enabled it for performance benefits without fully considering the security implications, making them more susceptible to exploitation. Network administrators and security teams would need to carefully evaluate their deployment of HTTP/2 features and assess whether the vulnerability could be leveraged to bypass security controls or access sensitive data. The impact would be particularly severe for web applications that depend on the proxy server for traffic management and security enforcement.
Organizations should immediately upgrade to Apache Traffic Server version 5.3.2 or later to remediate this vulnerability, as this represents the first official release that addresses the security issue. System administrators should also conduct thorough assessments of their current deployments to determine if the HTTP/2 experimental feature is actively being used and whether any additional security measures are needed. The vulnerability demonstrates the importance of carefully evaluating experimental features before deploying them in production environments, as these features often lack the comprehensive security testing applied to stable releases. Security teams should implement monitoring for unusual HTTP/2 traffic patterns or connection behavior that might indicate exploitation attempts. Additionally, organizations should consider disabling the HTTP/2 experimental feature until they can confirm it has been properly patched and tested in their specific operational environment. The incident highlights the need for organizations to maintain current security awareness and to regularly update their software components, particularly those implementing experimental or emerging protocol standards that may contain undiscovered vulnerabilities.
This vulnerability aligns with CWE categories related to protocol implementation flaws and security weaknesses in network protocols, specifically addressing issues in HTTP/2 protocol handling. From an ATT&CK perspective, this vulnerability could enable techniques such as privilege escalation through protocol manipulation, denial of service attacks, or information gathering through connection state manipulation. The experimental nature of the feature makes it particularly susceptible to these types of issues, as such features often bypass normal security review processes. Organizations should also consider the broader implications for their security posture when implementing experimental features, as these may introduce unknown risks that could be exploited by advanced persistent threat actors or automated attack tools.