Zimbra's Critical Security Update: Addressing SNMP Command Injection and XSS Vulnerabilities
In July 2026, Zimbra released version 10.1.20 to address multiple critical security vulnerabilities, including a command injection flaw in the SNMP monitoring component and four cross-site scripting (XSS) vulnerabilities in the Classic Web Client. These flaws could allow unauthenticated attackers to execute arbitrary OS commands and malicious scripts, potentially compromising email servers and user sessions. Additionally, a mail forwarding restriction bypass (CVE-2026-50055) was patched, which could have allowed authenticated users to exfiltrate emails despite restrictions being enabled. The prompt release of these patches underscores the importance of timely software updates to mitigate potential security risks. Organizations using Zimbra are advised to upgrade to version 10.1.20 immediately to protect against these vulnerabilities and maintain the integrity of their email systems.
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