CVE-2026-100520 in Laranode
Summary
by MITRE • 09/26/2026
Laranode versions before 1.2.1 contain a path traversal vulnerability in the POST /filemanager/upload-file endpoint that allows authenticated users to write arbitrary files outside their home directory. Attackers can supply directory traversal sequences in the path parameter to write PHP files into other tenants' web roots and execute code as those tenants.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 09/26/2026
Laranode versions prior to 1.2.1 are susceptible to a critical path traversal vulnerability within the POST /filemanager/upload-file endpoint, which fundamentally compromises the integrity of multi-tenant SaaS environments. This flaw arises from insufficient validation and sanitization of user-supplied input in the path parameter during file upload operations. Instead of strictly confining uploaded files to the designated tenant-specific directory structure, the application fails to properly normalize or restrict the destination path. Consequently, an authenticated attacker can manipulate this parameter by injecting standard Unix-style directory traversal sequences, such as ../..//, into the request payload. This manipulation allows the malicious actor to break out of their isolated sandbox and write arbitrary files directly into the web root directories belonging to other tenants within the same infrastructure.
The operational impact of this vulnerability is severe due to its potential for cross-tenant code execution. By successfully writing PHP scripts or other executable server-side content into a victim tenant's public-facing directory, an attacker gains the ability to execute custom code with the privileges associated with that specific tenant account. This effectively bypasses logical access controls designed to isolate customers in shared hosting environments. The vulnerability aligns closely with CWE-22: Improper Limitation of a Pathname to a Restricted Directory and is often categorized under ATT&CK technique T1505.003, which involves Server Side Web Framework Components for persistence or execution. In multi-tenant architectures, such as those built on Laravel frameworks where Laranode operates, this represents a catastrophic failure in tenant isolation mechanisms, potentially leading to data exfiltration, defacement of other tenants' websites, or further lateral movement within the underlying server infrastructure if additional privileges are escalated through the executed code.
Mitigation strategies must prioritize immediate patching and rigorous input validation practices. The most effective remediation is upgrading Laranode to version 1.2.1 or later, where this specific path traversal issue has been addressed by developers implementing stricter boundary checks on file paths. For organizations unable to upgrade immediately, defensive coding measures should be enforced at the application layer. This includes validating that the resolved absolute path of any uploaded file remains strictly within the expected tenant directory using canonicalization techniques before writing data to disk. Additionally, deploying a Web Application Firewall with rules capable of detecting and blocking common traversal sequences in upload parameters can provide an interim layer of defense. Regular security audits focusing on file handling logic are essential to ensure that future updates do not reintroduce similar flaws, maintaining the integrity of tenant isolation protocols across the platform.