CVE-2012-4449 in Hadoop
Summary
by MITRE
Apache Hadoop before 0.23.4, 1.x before 1.0.4, and 2.x before 2.0.2 generate token passwords using a 20-bit secret when Kerberos security features are enabled, which makes it easier for context-dependent attackers to crack secret keys via a brute-force attack.
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Analysis
by VulDB Data Team • 12/02/2019
Apache Hadoop versions prior to 0.23.4 in the 0.23.x series, 1.x versions before 1.0.4, and 2.x versions before 2.0.2 contain a critical cryptographic weakness in their token password generation mechanism when Kerberos security features are enabled. This vulnerability stems from the use of a 20-bit secret for generating token passwords, which significantly reduces the security strength of the authentication tokens. The weakness creates a substantial attack surface that allows context-dependent adversaries to perform brute-force attacks against the secret keys, potentially compromising the entire Hadoop cluster's security posture.
The technical flaw manifests in the cryptographic implementation where the system generates authentication tokens using insufficient entropy. A 20-bit secret provides only 2^20 possible combinations, which is computationally feasible for modern attackers to exhaustively search through within reasonable timeframes. This weakness directly violates established cryptographic best practices and security standards such as those outlined in CWE-326, which addresses inadequate encryption strength. The vulnerability is particularly dangerous in distributed computing environments where Hadoop clusters handle sensitive data and require robust authentication mechanisms to prevent unauthorized access.
The operational impact of this vulnerability extends beyond simple credential theft, as successful exploitation can lead to complete cluster compromise and unauthorized data access. Attackers can leverage this weakness to bypass Kerberos authentication, gain elevated privileges, and potentially move laterally within the network infrastructure. This represents a significant threat to organizations relying on Hadoop for big data processing, as the compromised authentication tokens could provide attackers with persistent access to large-scale distributed systems. The vulnerability aligns with ATT&CK technique T1550.001, which covers legitimate credentials usage through Kerberos ticket manipulation.
Organizations should immediately implement mitigations including upgrading to patched versions of Apache Hadoop, specifically versions 0.23.4, 1.0.4, and 2.0.2 or later, which address the insufficient entropy issue. Additionally, security teams should consider implementing additional monitoring for authentication anomalies and strengthen overall cluster security through network segmentation and access controls. The fix ensures that token passwords are generated using cryptographically secure random number generators with sufficient entropy, typically at least 128 bits or higher, to prevent brute-force attacks. Organizations should also conduct thorough security assessments to identify any potential exploitation attempts and implement comprehensive audit logging to detect unauthorized access attempts.