CVE-2026-73570 in Collaboration
Summary
by MITRE • 08/13/2026
A remote code execution vulnerability exists in Zimbra Collaboration (ZCS) before 10.1.20 when the optional zimbra-snmp package is installed and SNMP notifications are enabled. Due to improper sanitization of untrusted input during SNMP notification processing, an unauthenticated attacker can send specially crafted SMTP requests that may result in execution of arbitrary operating system commands as the Zimbra user.
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Analysis
by VulDB Data Team • 08/13/2026
This vulnerability represents a critical remote code execution flaw in Zimbra Collaboration Suite versions prior to 10.1.20 that specifically manifests when the zimbra-snmp package is installed and SNMP notifications are enabled. The issue stems from inadequate input validation within the SNMP notification processing mechanism, creating a pathway for malicious actors to execute arbitrary commands on the affected system. The vulnerability operates through the SMTP subsystem where untrusted input from external sources is not properly sanitized before being processed in the context of SNMP notification handling, making it particularly dangerous as it requires no authentication to exploit.
The technical flaw resides in the improper sanitization of untrusted input during SNMP notification processing, which creates a command injection vulnerability that can be triggered through specially crafted SMTP requests. When these malicious requests are received and processed, they bypass normal input validation checks and are interpreted by the underlying operating system as executable commands. This weakness aligns with common software security vulnerabilities classified under CWE-77 and CWE-94 in the Common Weakness Enumeration framework, specifically addressing improper input sanitization leading to command injection and arbitrary code execution. The attack vector leverages the SNMP notification infrastructure to deliver malicious payloads that exploit the lack of proper input validation in the processing pipeline.
The operational impact of this vulnerability is severe as it allows unauthenticated remote attackers to execute arbitrary commands with the privileges of the Zimbra user account, which typically has significant system access rights. This could enable attackers to gain full control over the affected server, potentially leading to data breaches, system compromise, and further lateral movement within the network. The vulnerability affects organizations using Zimbra Collaboration Suite with SNMP notifications enabled, creating a persistent threat vector that can be exploited without prior authentication or credentials. The implications extend beyond immediate system compromise to include potential data exfiltration and establishment of persistent backdoors through the executed commands.
Organizations should immediately upgrade to Zimbra Collaboration Suite version 10.1.20 or later to remediate this vulnerability, as no effective workarounds exist for the specific flaw in SNMP notification processing. The recommended mitigation strategy involves disabling the zimbra-snmp package if SNMP notifications are not actively required, or ensuring that SNMP functionality is properly secured with appropriate network segmentation and access controls. Security teams should implement monitoring for unusual SMTP traffic patterns and establish network-level controls to restrict access to SNMP ports and related services. Additionally, organizations should conduct comprehensive security assessments of their Zimbra installations to identify any other potential vulnerabilities in the SNMP notification processing components, aligning with ATT&CK framework techniques related to command execution and privilege escalation through insecure service configurations.