CVE-2013-2944 in strongSwan
Summary
by MITRE
strongSwan 4.3.5 through 5.0.3, when using the OpenSSL plugin for ECDSA signature verification, allows remote attackers to authenticate as other users via an invalid signature.
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Analysis
by VulDB Data Team • 12/26/2024
The vulnerability identified as CVE-2013-2944 affects strongSwan implementations version 4.3.5 through 5.0.3 that utilize the OpenSSL plugin for ECDSA signature verification. This represents a critical security flaw in the Internet Key Exchange protocol implementation that could enable unauthorized authentication and privilege escalation. The issue stems from improper validation of ECDSA signatures within the cryptographic verification process, creating a pathway for malicious actors to exploit the system's trust mechanisms.
The technical flaw manifests in the OpenSSL plugin's handling of ECDSA signature verification where the implementation fails to properly validate the signature structure and parameters. When processing authentication requests, the system accepts malformed or invalid signatures that should have been rejected during the verification phase. This weakness allows attackers to craft specially crafted signatures that bypass the normal cryptographic validation checks, effectively enabling them to authenticate as legitimate users within the IPSec network infrastructure. The vulnerability specifically impacts the cryptographic verification process and can be categorized under CWE-290 authentication bypass weakness.
The operational impact of this vulnerability is severe as it fundamentally undermines the security model of IPSec-based authentication systems. Attackers can leverage this flaw to impersonate legitimate users and gain unauthorized access to protected network resources, potentially leading to complete network compromise. The vulnerability affects the integrity and authenticity guarantees that ECDSA signatures are designed to provide, creating a persistent threat vector that could remain undetected for extended periods. This weakness particularly impacts organizations relying on strongSwan for secure remote access and site-to-site connections where user authentication is critical for network security.
Mitigation strategies should focus on immediate patching of affected strongSwan versions to 5.1.0 or later where the vulnerability has been addressed through proper signature validation implementation. Organizations should also implement additional monitoring and logging of authentication events to detect anomalous signature validation patterns. Network segmentation and additional authentication layers should be considered as temporary compensating controls. The vulnerability aligns with ATT&CK technique T1550.001 for legitimate credentials and T1078 for valid accounts, making it particularly dangerous in environments where privilege escalation and lateral movement are concerns. Security teams should also review and audit existing ECDSA certificate configurations to ensure proper implementation of cryptographic standards and validate that all signature verification processes properly enforce cryptographic integrity checks.