Path Traversal Vulnerability in Mattermost Leading to Arbitrary File Writing

CVE-2025-4981

What is CVE-2025-4981?

CVE-2025-4981 is a path traversal vulnerability identified in Mattermost, an open-source messaging platform designed for team collaboration. The vulnerability affects several versions of Mattermost, specifically those where file uploads and content extraction features are enabled—settings that are typically activated by default. This issue arises because the software fails to properly sanitize filenames when extracting archive files. As a result, authenticated users can exploit this vulnerability to write files to arbitrary locations within the system's file structure, potentially leading to remote code execution and unauthorized access to sensitive data.

Organizations that rely on Mattermost for communication and collaboration may experience significant operational disruptions if this vulnerability is exploited. The ability for a malicious actor to manipulate file locations can lead to data loss, system compromise, and a cascading effect on overall security posture.

Potential impact of CVE-2025-4981

1. Remote Code Execution: The most alarming consequence of this vulnerability is the potential for remote code execution. Attackers could use this flaw to execute arbitrary commands on the server, leading to full system compromise.

2. Data Integrity Risks: Since attackers can write to arbitrary file paths, there's a substantial risk of data manipulation or corruption. This could compromise the integrity of sensitive information and impact organizational decision-making.

3. Increased Attack Surface: The existence of this vulnerability can make organizations more susceptible to subsequent attacks. By exploiting CVE-2025-4981, threat actors may gain a foothold in the network, allowing for the deployment of additional malware or ransomware, further endangering the organization’s critical systems and data.

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