CVE-2023-43300 in mini-app on Line
Summary
by MITRE • 12/07/2023
An issue in urban_project mini-app on Line v13.6.1 allows attackers to send crafted malicious notifications via leakage of the channel access token.
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Analysis
by VulDB Data Team • 12/30/2023
The vulnerability identified as CVE-2023-43300 represents a critical security flaw within the urban_project mini-app ecosystem running on Line messaging platform version 13.6.1. This issue stems from improper handling of channel access tokens which are fundamental credentials used for authenticating and authorizing communication between applications and the Line messaging infrastructure. The flaw allows malicious actors to exploit information leakage mechanisms that expose these sensitive authentication tokens, thereby compromising the security boundaries of the mini-app environment.
The technical implementation of this vulnerability involves the unauthorized disclosure of channel access tokens through notification delivery mechanisms within the Line platform. These tokens serve as bearer credentials that grant full access to messaging channels and associated functionalities. When attackers can obtain these tokens through crafted malicious notifications, they essentially gain the ability to impersonate legitimate applications and execute unauthorized operations within the Line ecosystem. The flaw operates at the intersection of information disclosure and authentication bypass, creating a pathway for privilege escalation and unauthorized access to communication channels.
From an operational impact perspective, this vulnerability enables attackers to perform several malicious activities including sending spam notifications, conducting phishing attacks, and potentially accessing sensitive user data through the compromised communication channels. The exploitation of this vulnerability can lead to widespread abuse of the Line messaging platform as attackers can leverage the stolen tokens to send notifications to any user within the scope of the compromised channel. This creates a significant risk for both individual users and organizations that rely on Line for business communications, as the attackers can effectively bypass normal access controls and authentication mechanisms.
The vulnerability aligns with CWE-200, which addresses information exposure, and demonstrates characteristics consistent with CWE-306, authentication bypass. From an adversarial perspective, this flaw maps to ATT&CK technique T1078.004, which covers legitimate credentials, and T1566, which involves phishing and social engineering. The attack surface is particularly concerning as it leverages the trust relationship inherent in the Line platform's notification system, allowing attackers to operate within the legitimate communication framework while executing malicious activities.
Mitigation strategies should focus on implementing proper token management practices, including regular token rotation, implementing strict access controls, and monitoring for unusual notification patterns. Organizations should also consider implementing additional authentication layers and conducting regular security assessments of their mini-app implementations. The Line platform itself should enhance its token validation mechanisms and implement rate limiting for notification delivery to prevent abuse of the notification system. Security teams should also establish monitoring protocols to detect unauthorized token usage and implement incident response procedures to quickly address potential exploitation attempts.