CVE-2004-2579 in Internet Explorer
Summary
by MITRE
ACLCHECK module in Novell iChain 2.3 allows attackers to bypass access control rules of an unspecified component via an unspecified attack vector involving a string that contains escape sequences represented with "overlong UTF-8 encoding."
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Analysis
by VulDB Data Team • 03/15/2021
The CVE-2004-2579 vulnerability resides within the ACLCHECK module of Novell iChain 2.3, a web access management solution designed to enforce security policies and control access to network resources. This flaw represents a critical bypass vulnerability that undermines the fundamental security mechanisms intended to protect organizational networks. The vulnerability specifically targets the access control enforcement capabilities of the system, potentially allowing unauthorized users to circumvent established security policies and gain access to restricted resources. The issue manifests through an unusual attack vector involving string manipulation with overlong UTF-8 encoding sequences that can confuse the access control evaluation process. The unspecified nature of both the affected component and attack vector suggests this vulnerability may have broader implications across multiple security controls within the iChain framework. This type of vulnerability directly violates the principle of least privilege and can lead to unauthorized data access, system compromise, and potential lateral movement within affected networks.
The technical exploitation of this vulnerability relies on the manipulation of UTF-8 encoding sequences to craft malicious input that can evade the access control checks implemented by the ACLCHECK module. When the system processes strings containing overlong UTF-8 encoding representations, the access control evaluation logic fails to properly normalize or validate these sequences, creating a path for attackers to bypass security restrictions. This behavior aligns with CWE-116, which addresses improper encoding of control characters and highlights the dangers of inadequate input sanitization in security-critical systems. The vulnerability demonstrates how character encoding inconsistencies can be weaponized to bypass security controls, particularly when the system's validation logic does not properly account for all valid representations of the same character. Attackers can leverage this weakness by crafting requests that contain specially formatted UTF-8 sequences that, when processed by the ACLCHECK module, result in incorrect access control decisions. The overlong UTF-8 encoding technique exploits the fact that certain characters can be represented in multiple ways within UTF-8, creating ambiguity in the validation process that malicious actors can manipulate for unauthorized access.
The operational impact of CVE-2004-2579 extends beyond simple unauthorized access, potentially enabling attackers to escalate privileges and move laterally within the network infrastructure. Organizations relying on Novell iChain for web access control may experience complete compromise of their security posture, as the vulnerability undermines the core function of access control enforcement. This weakness can lead to data breaches, unauthorized system modifications, and potential exfiltration of sensitive information from protected resources. The vulnerability's potential for exploitation is heightened by the fact that it operates at the policy enforcement level, meaning that successful attacks could bypass multiple layers of security controls that should normally protect network resources. Security teams may face challenges in detecting exploitation attempts, as the malicious activity could appear as legitimate traffic with unusual but valid encoding patterns. The impact is particularly severe in environments where iChain serves as a central access control point for critical applications and data repositories, as compromise of this system could provide attackers with a foothold for broader network infiltration.
Mitigation strategies for CVE-2004-2579 should focus on immediate patching of the Novell iChain 2.3 software to address the underlying access control bypass vulnerability. Organizations should implement comprehensive input validation policies that normalize all character encoding before processing, particularly focusing on UTF-8 sequence validation to prevent overlong encoding exploitation. Network segmentation and additional access control layers should be implemented to reduce the potential impact of any successful exploitation attempts. Security monitoring should be enhanced to detect unusual UTF-8 encoding patterns in access control requests, as part of broader network traffic analysis. The vulnerability also highlights the importance of proper security testing for character encoding handling in security-critical applications, aligning with ATT&CK technique T1078 for valid accounts and T1566 for credential harvesting through network-based attacks. Organizations should conduct thorough security assessments of their access control systems to identify similar encoding-related vulnerabilities that may exist in other components of their security infrastructure. Regular security updates and vulnerability management processes should be strengthened to ensure timely remediation of such critical access control bypass vulnerabilities.