CVE-2018-7050 in irssi
Summary
by MITRE
An issue was discovered in Irssi before 1.0.7 and 1.1.x before 1.1.1. A NULL pointer dereference occurs for an "empty" nick.
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Analysis
by VulDB Data Team • 02/08/2023
The vulnerability identified as CVE-2018-7050 represents a critical NULL pointer dereference flaw affecting the Irssi IRC client software across multiple versions. This issue manifests specifically when processing an "empty" nickname within the client's communication framework, creating a potential crash condition that could be exploited by malicious actors. The vulnerability exists in Irssi versions prior to 1.0.7 and 1.1.x versions before 1.1.1, indicating a widespread impact across the software's release history. The flaw demonstrates characteristics consistent with CWE-476, which describes NULL pointer dereference conditions that can lead to application instability and potential system compromise.
The technical implementation of this vulnerability stems from insufficient input validation within Irssi's nickname handling mechanisms. When the client encounters an empty nickname during IRC protocol processing, the software fails to properly validate the pointer reference before attempting to dereference it. This occurs in the context of IRC message parsing where the application expects a valid nickname string but receives a NULL value instead. The NULL pointer dereference creates a memory access violation that results in an application crash, effectively causing a denial of service condition for legitimate users. This type of vulnerability falls under the ATT&CK technique T1499.004, which covers network denial of service attacks through application crashes.
The operational impact of CVE-2018-7050 extends beyond simple service disruption as it represents a potential vector for more sophisticated attacks within IRC environments. In multi-user chat scenarios, an attacker could exploit this vulnerability to repeatedly crash client sessions, disrupting communication channels and potentially affecting collaborative workspaces. The vulnerability's presence in widely-used IRC client software means that organizations relying on IRC for internal communications or external coordination could face significant operational disruptions. The issue also highlights the importance of proper input sanitization in network applications, particularly those handling user-generated content in real-time communication systems.
Mitigation strategies for CVE-2018-7050 primarily involve immediate software updates to versions 1.0.7 or 1.1.1 and later, which contain the necessary patches to address the NULL pointer dereference. System administrators should prioritize patching all instances of Irssi across their networks, particularly in environments where IRC clients are actively used for business communications. Additionally, implementing network monitoring solutions that can detect unusual client crash patterns may help identify potential exploitation attempts. The vulnerability serves as a reminder of the critical importance of input validation in network applications, aligning with security best practices outlined in the OWASP Top Ten and similar industry standards. Organizations should also consider implementing application firewalls or intrusion detection systems that can monitor for malformed IRC protocol messages that might trigger this specific vulnerability.