CVE-2026-78971 in Halo
Summary
by MITRE • 09/09/2026
In Halo <= 2.25.4, the plugin management feature allows users to install/update malicious plugins, which could let attackers execute any command with Halo process permissions.
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Analysis
by VulDB Data Team • 09/09/2026
The vulnerability identified in Halo versions prior to or equal to 2.25.4 represents a critical failure in access control and input validation within the application's plugin management subsystem. This flaw stems from an insufficient verification mechanism that permits users, potentially including those with lower privilege levels such as standard editors or contributors depending on the specific configuration of the instance, to install or update plugins without adequate administrative oversight or integrity checks. The core technical deficiency lies in the lack of strict authorization enforcement and code signing validation for plugin artifacts during installation and update processes. By allowing arbitrary plugin uploads from untrusted sources or by failing to restrict this capability exclusively to trusted administrators with verified identities, the system inadvertently provides a direct pathway for remote attackers to inject malicious code into the application environment. This misconfiguration effectively bypasses intended security boundaries, transforming a standard content management feature into an execution vector for severe compromise.
From a technical perspective, the exploitation of this vulnerability allows an attacker to achieve arbitrary command execution with the same privileges as the Halo process itself. When a user installs or updates a plugin through the vulnerable interface, they can supply crafted code that executes system-level commands upon activation or even during installation depending on how the runtime environment handles dynamic loading. This capability grants the adversary full control over the underlying operating system processes running Halo, enabling them to read sensitive configuration files, exfiltrate database credentials stored in plaintext or weakly encrypted formats, modify application logic, and pivot further into the internal network infrastructure. The severity is amplified by the fact that web applications often run with elevated permissions relative to standard user accounts but may not be hardened against lateral movement once initial access is gained through such a high-privilege execution flaw.
The operational impact of this vulnerability extends beyond immediate data theft or service disruption, posing significant risks to organizational integrity and compliance posture. An attacker leveraging this command injection can establish persistent backdoors by modifying startup scripts or creating scheduled tasks that survive application restarts. Furthermore, because plugins often interact with databases and external APIs, the compromise facilitates broader system infiltration where sensitive user data, intellectual property, and proprietary business logic are at risk of exposure. In regulated industries, such a breach could trigger violations of standards like GDPR, HIPAA, or PCI-DSS due to unauthorized access to protected information. The ability to execute commands as the application process also means that attackers can potentially escalate privileges further if the Halo service runs with root or administrator rights on the host machine, leading to complete system takeover and potential botnet recruitment for distributed denial-of-service attacks or cryptomining operations.
To mitigate this risk, immediate remediation requires upgrading the Halo installation to a version greater than 2.25.4 where these access control flaws have been addressed by developers through stricter role-based access controls and enhanced plugin verification protocols. In environments where patching is not immediately feasible, administrators should enforce network-level restrictions to limit outbound connections from the application server and restrict file upload capabilities within the admin interface until an update can be applied. It is also advisable to review audit logs for any suspicious plugin installations or updates that occurred prior to remediation, checking for indicators of compromise such as unusual process executions or new files in web directories. Implementing a Web Application Firewall with rules targeting known exploitation patterns related to file uploads and command injection can provide an additional layer of defense while the underlying vulnerability is resolved.
This incident aligns with several established industry standards regarding software security flaws. Specifically, it corresponds to CWE-269 Improper Privilege Management, as the application failed to enforce appropriate separation of duties between administrative functions and user actions. Additionally, the mechanism exploited relates closely to CWE-434 Unrestricted Upload of File with Dangerous Type, given that plugins are essentially executable code packages being uploaded without sufficient validation. From a tactical standpoint, this vulnerability facilitates techniques documented in the MITRE ATT&CK framework under Initial Access via Valid Accounts (T1078) and Execution via Remote Services or Command Line Interface (T1059), highlighting how misconfigured administrative features can serve as primary entry points for advanced persistent threats seeking to establish footholds within enterprise networks.