CVE-2026-67609 in TVox
Summary
by MITRE • 08/03/2026
Telenia Software TVox 26.5.3 and prior 26.x versions, and 24.9.21 and prior 24.x versions, contain a privilege escalation vulnerability that allows attackers with access to the apache account to execute arbitrary commands as root by exploiting an insecure sudoers configuration in /etc/sudoers.d/telenia. The configuration grants the apache user NOPASSWD execution of /bin/nice, which can be leveraged to invoke arbitrary commands, enabling full root-level command execution without supplying a password.
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Analysis
by VulDB Data Team • 08/03/2026
This vulnerability represents a critical privilege escalation flaw in Telenia Software TVox versions prior to 26.5.3 and 24.9.21, where attackers with access to the apache user account can achieve full system compromise through insecure sudoers configuration. The vulnerability stems from an improperly configured sudoers file located at /etc/sudoers.d/telenia which grants the apache user unrestricted NOPASSWD execution privileges for the /bin/nice command. This misconfiguration creates a dangerous attack vector that directly violates security principle of least privilege, as the apache user should not have elevated permissions to execute system-level commands without authentication.
The technical exploitation mechanism relies on the fact that /bin/nice is a utility designed to run programs with modified scheduling priority, but it can be manipulated to execute arbitrary commands when combined with proper command chaining or argument injection techniques. According to CWE-276, this vulnerability maps directly to inadequate privileges for critical operations, specifically CWE-276 which addresses improper privilege management. The flaw enables attackers to bypass normal authentication mechanisms and achieve root-level access through a simple command execution sequence that leverages the NOPASSWD directive.
From an operational perspective, this vulnerability provides attackers with complete system control without requiring additional credentials or complex exploitation techniques. The attack surface is significantly reduced since only apache user access is needed to initiate the escalation process, making it particularly dangerous in environments where web server accounts are more easily compromised than privileged accounts. This vulnerability aligns with ATT&CK technique T1068 which describes local privilege escalation through the use of sudo or other system privileges, and T1548.003 which covers abuse of sudoers configuration files for privilege escalation.
The impact extends beyond simple command execution as it allows full persistence and reconnaissance capabilities once root access is achieved. Attackers can modify system files, install backdoors, exfiltrate sensitive data, or establish covert communication channels without detection. Organizations running affected versions face significant risk of complete system compromise, particularly in environments where apache accounts are accessible through web application attacks or other initial compromise vectors. The vulnerability demonstrates poor security hygiene in privilege management and highlights the critical importance of regular security audits of sudoers configurations.
Mitigation strategies should include immediate patching to the latest available versions of Telenia Software TVox, followed by comprehensive review and remediation of all sudoers configurations. Security teams must implement strict access controls for web server accounts, ensuring that apache users have minimal required privileges and that no NOPASSWD directives exist for system-critical commands. Additionally, organizations should conduct regular security assessments of privilege configurations and implement monitoring solutions to detect unauthorized sudo usage patterns. The vulnerability underscores the necessity of following defense-in-depth principles and maintaining strict separation between different system roles and their respective privilege levels.