CVE-2026-27555 Overview
CVE-2026-27555 is a local file inclusion (LFI) vulnerability affecting the /index.php/ajax/get_iodd_port_info endpoint. A low-privileged remote attacker holding a valid user cookie can exploit the flaw to include and execute arbitrary PHP code on the device. The weakness is classified under CWE-98, which covers improper control of filename for include/require statements in PHP. Successful exploitation grants full read, write, and execution impact on the affected system. The vulnerability is tracked by CERT-VDE across three related advisories.
Critical Impact
Authenticated attackers can achieve arbitrary PHP code execution over the network, leading to complete compromise of confidentiality, integrity, and availability on the affected device.
Affected Products
- Devices exposing the /index.php/ajax/get_iodd_port_info PHP endpoint (see CERT-VDE advisories)
- Product details listed in CERT-VDE Advisory VDE-2026-014
- Additional affected products in CERT-VDE Advisory VDE-2026-027 and CERT-VDE Advisory VDE-2026-028
Discovery Timeline
- 2026-09-16 - CVE-2026-27555 published to NVD
- 2026-09-16 - Last updated in NVD database
Technical Details for CVE-2026-27555
Vulnerability Analysis
The vulnerability resides in the get_iodd_port_info AJAX handler exposed through /index.php/ajax/get_iodd_port_info. The handler passes attacker-controlled input into a PHP include or require statement without adequate validation. An attacker with a valid session cookie can point the include target at a PHP file already on disk or delivered through log poisoning, session files, or upload mechanisms. Once included, the PHP interpreter executes the referenced code with the privileges of the web application. The result is arbitrary code execution on the device, which typically grants the attacker equivalent access to the web service account.
Root Cause
The root cause is improper control of filename passed to a PHP include directive, categorized as CWE-98. The endpoint concatenates user-supplied data into a filesystem path used for dynamic file inclusion. No allowlist, canonicalization, or path restriction limits which files the interpreter can load. Because PHP evaluates included files as code, any file containing PHP directives becomes an execution primitive.
Attack Vector
Exploitation requires network access to the web interface and a valid authenticated user cookie. The attacker sends a crafted HTTP request to /index.php/ajax/get_iodd_port_info with a parameter that manipulates the include path. Traversal sequences or absolute paths redirect the include to attacker-controlled content. Because privileges required are low, any legitimate user account is sufficient to trigger the flaw. Refer to the CERT-VDE advisories for endpoint-specific parameter details.
Stop Remote Code Execution Before It Runs
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Stop Exploit AttemptsDetection Methods for CVE-2026-27555
Indicators of Compromise
- HTTP requests to /index.php/ajax/get_iodd_port_info containing path traversal sequences such as ../, absolute filesystem paths, or references to log, session, or upload directories.
- Unexpected PHP processes spawning shell interpreters, network utilities, or reverse-shell binaries from the web server context.
- New or modified files in web-accessible directories that were not deployed by the vendor.
Detection Strategies
- Inspect web server access logs for authenticated requests to the get_iodd_port_info endpoint carrying suspicious query or POST parameters.
- Correlate authenticated session activity with unusual file reads outside the application document root.
- Deploy endpoint behavioral monitoring on the affected device to flag PHP-initiated child processes that deviate from baseline application behavior.
Monitoring Recommendations
- Enable verbose logging on the web server and forward logs to a centralized platform for retention and correlation.
- Alert on authenticated sessions issuing repeated requests to the vulnerable endpoint within short time windows.
- Track outbound network connections initiated by the web service account to detect post-exploitation callbacks.
How to Mitigate CVE-2026-27555
Immediate Actions Required
- Apply the vendor firmware or software updates referenced in CERT-VDE Advisory VDE-2026-014, VDE-2026-027, and VDE-2026-028 as soon as they are available.
- Restrict network access to the management web interface to trusted administrative networks only.
- Rotate credentials for all user accounts and invalidate active sessions on affected devices.
Patch Information
Refer to the three CERT-VDE advisories for vendor-supplied patched firmware or software versions. Because the enriched CVE data does not list specific fixed versions, administrators should consult the linked advisories directly to confirm the applicable release for their product model.
Workarounds
- Place the affected web interface behind a VPN or reverse proxy that enforces additional authentication and IP allowlisting.
- Remove or disable low-privileged user accounts that do not require access to the management interface.
- Monitor and alert on any access to /index.php/ajax/get_iodd_port_info until patches are applied.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
