Cloud Vulnerability DB
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Vulnerability DatabaseCVE-2025-20621
CVE-2025-20621:
Chainguard vulnerability analysis and mitigation
Overview
Mattermost versions 10.2.x <= 10.2.0, 9.11.x <= 9.11.5, 10.0.x <= 10.0.3, and 10.1.x <= 10.1.3 contain a vulnerability related to improper validation of specified type of input (CWE-1287). The vulnerability was disclosed on December 16, 2024, and has been assigned CVE-2025-20621 (NVD, Mattermost).
Technical details
The vulnerability stems from the application's failure to properly handle posts with attachments containing fields that cannot be cast to a String. The issue has been assigned a CVSS v3.1 base score of 6.5 (Medium) with the vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (NVD).
Impact
When exploited, this vulnerability allows an attacker to cause the webapp to crash by creating and sending a post with specially crafted attachments to a channel. The impact is limited to availability with no direct effect on confidentiality or integrity (Mattermost).
Mitigation and workarounds
The vulnerability has been fixed in Mattermost versions 10.3.0, 10.2.1, 9.11.6, 10.0.4, and 10.1.4. Users are advised to upgrade to these or later versions to mitigate the vulnerability (Mattermost).
Additional resources
Source: This report was generated using AI
Related Chainguard vulnerabilities:
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