CVE-2002-1840 in irssi
Summary
by MITRE
irssi IRC client 0.8.4, when downloaded after 14-March-2002, could contain a backdoor in the configuration file, which allows remote attackers to access the system.
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Analysis
by VulDB Data Team • 07/04/2024
The vulnerability identified as CVE-2002-1840 represents a significant security flaw in the irssi IRC client version 0.8.4 that was released after March 14, 2002. This backdoor mechanism was embedded within the configuration file of the software, creating a covert pathway for remote attackers to gain unauthorized access to systems running the compromised version. The vulnerability specifically exploited the trust model inherent in IRC client software, where users typically download and execute configuration files without thorough security verification. This particular backdoor was not a runtime vulnerability but rather a supply chain compromise that occurred during the software distribution process, making it particularly insidious as it could affect any user who downloaded the software during the specified timeframe.
The technical implementation of this backdoor involved malicious code embedded within the configuration file that would execute when the irssi client was launched. This configuration file would contain commands or code segments that, when processed by the client, would establish remote access capabilities. The flaw operated at the application level and leveraged the trust users placed in legitimate software downloads. According to CWE classification, this vulnerability aligns with CWE-494, which deals with the download of code without integrity checking, and CWE-94, which addresses the execution of arbitrary code. The backdoor functionality would typically allow attackers to execute commands on the compromised system, potentially leading to full system compromise and persistent access. The vulnerability exploited the principle of least privilege by enabling unauthorized remote code execution through legitimate software channels.
The operational impact of CVE-2002-1840 was substantial across the IRC community and beyond, as irssi was widely used for communication in various technical and organizational contexts. The vulnerability created a persistent threat vector that could remain undetected for extended periods, as the backdoor would operate silently in the background. Network administrators and security professionals faced the challenge of identifying compromised systems without direct evidence of attack, as the backdoor would not necessarily generate obvious network traffic patterns. The attack pattern described in the MITRE ATT&CK framework would align with T1078 for valid accounts and T1566 for social engineering, as users would unknowingly execute compromised code through legitimate software downloads. Organizations relying on IRC for communication, development coordination, or administrative purposes were particularly vulnerable, as the backdoor could provide attackers with persistent access to sensitive communication channels and potentially compromise entire network infrastructures.
Mitigation strategies for this vulnerability required immediate action including software updates, configuration file verification, and comprehensive system auditing. Users needed to obtain fresh copies of the irssi client from trusted sources and verify the integrity of downloaded files using cryptographic checksums or digital signatures. Security professionals should have implemented network monitoring to detect unusual outbound connections that might indicate backdoor activity. The incident highlighted the critical importance of software supply chain security and integrity verification processes. Organizations needed to establish procedures for validating software authenticity and implementing security controls around software distribution. This vulnerability underscored the necessity of maintaining updated software inventories and conducting regular security assessments of all installed applications to prevent similar supply chain compromises from affecting operational security. The incident served as a catalyst for improved software distribution security practices and the adoption of more robust integrity verification mechanisms in software delivery processes.