CVE-2025-54798 Vulnerability In Tmp: What You Need To Know

by Kenji Nakamura 59 views

Hey guys! Let's dive into a security vulnerability that has been identified in the tmp-0.0.33.tgz library. This is a low-severity issue, but it's still important to understand what's going on and how it might affect your projects. So, let’s get started!

Understanding the Vulnerability

This vulnerability, CVE-2025-54798, affects the tmp library, specifically version 0.0.33.tgz. The tmp library is a handy tool for Node.js developers, allowing for the creation of temporary files and directories. This is super useful in many scenarios, like when you need a temporary space to process data or store files during an operation.

The core of the issue lies in a potential arbitrary file/directory write through a symbolic link. Essentially, this means that an attacker could potentially manipulate the way temporary files and directories are created, possibly leading to unwanted files being written in unexpected locations. While it’s a low-severity issue, it’s something we definitely want to address to keep our applications secure.

Vulnerable Library: tmp-0.0.33.tgz

  • Description: Temporary file and directory creator.
  • Library Home Page: https://registry.npmjs.org/tmp/-/tmp-0.0.33.tgz
  • Path to Dependency File: /templates/react-website-template/app/package.json
  • Path to Vulnerable Library: /templates/react-website-template/app/node_modules/tmp/package.json

Dependency Hierarchy

To really understand how this vulnerability impacts your project, it’s crucial to look at the dependency chain. In this case, the vulnerable library is nested within a series of dependencies:

  • react-scripts-2.1.8.tgz (Root Library)
    • eslint-5.12.0.tgz
      • inquirer-6.5.2.tgz
        • external-editor-3.1.0.tgz
          • :x: tmp-0.0.33.tgz (Vulnerable Library)

This means that the tmp library is a dependency of external-editor, which is a dependency of inquirer, and so on, ultimately being used by react-scripts. Tracing these dependencies helps us pinpoint exactly where the vulnerability is being introduced into the project.

The vulnerability was identified in the develop branch, indicating it's present in the current development codebase.

Vulnerability Details

The specifics of this vulnerability relate to how the tmp library handles the creation of temporary files and directories. In versions prior to 0.2.4, there's a flaw where the dir parameter, used to specify the directory for temporary file creation, can be exploited using symbolic links. A symbolic link, or symlink, is essentially a shortcut to another file or directory. By manipulating this, an attacker could potentially force the tmp library to write files or directories to unintended locations.

The vulnerability description highlights that tmp is vulnerable to an arbitrary temporary file / directory write via symbolic link dir parameter. This is a critical detail because it specifies the exact mechanism of the exploit. The good news is that this issue has been fixed in version 0.2.4 of the tmp library.

CVSS 3 Score Details (2.5)

The Common Vulnerability Scoring System (CVSS) is a standardized way to measure the severity of security vulnerabilities. In this case, CVE-2025-54798 has a CVSS 3 score of 2.5, which classifies it as a Low severity vulnerability. Let's break down the components that contribute to this score:

Base Score Metrics

The base score is calculated based on several factors related to the exploitability and impact of the vulnerability.

  • Exploitability Metrics:
    • Attack Vector: Local: This means the attacker needs to have local access to the system to exploit the vulnerability. It's not something that can be done remotely over the internet, which reduces the risk.
    • Attack Complexity: High: Exploiting this vulnerability is not straightforward. It requires specific conditions and likely some level of technical expertise, making it harder to exploit.
    • Privileges Required: Low: An attacker with low-level privileges on the system can potentially exploit this. This means they don't need to be an administrator or have special permissions.
    • User Interaction: None: The vulnerability can be exploited without any interaction from the user. This makes it potentially more dangerous, as an attacker doesn't need to trick a user into doing something.
    • Scope: Unchanged: The vulnerability affects only the component in which it exists, without affecting other parts of the system.
  • Impact Metrics:
    • Confidentiality Impact: None: The vulnerability doesn't allow an attacker to gain access to confidential information.
    • Integrity Impact: Low: An attacker could potentially modify some data or files, but the impact is limited.
    • Availability Impact: None: The vulnerability doesn't cause any disruption to the availability of the system.

Given these metrics, the low CVSS score makes sense. While the vulnerability exists, the requirements for exploitation are relatively high, and the potential impact is limited.

For more information on CVSS3 Scores, you can check out the CVSS calculator here.

How to Address the Vulnerability

So, what can you do to address this vulnerability? The most straightforward approach is to update the tmp library to version 0.2.4 or later. Since the vulnerability has been fixed in this version, upgrading will eliminate the risk. But how do you do that, especially when it’s buried in a dependency chain?

Updating Dependencies

  1. Check Your Package Manager: If you're using npm or yarn, you can use commands like npm update or yarn upgrade to update your dependencies. However, this might not always update nested dependencies to the latest versions due to version constraints specified in your package.json file.

  2. Use Dependency Management Tools: Tools like npm-check-updates or yarn upgrade-interactive can help you identify and update dependencies more effectively. These tools allow you to interactively choose which dependencies to update, including nested ones.

  3. Override Dependencies: In some cases, you might need to override the version of a nested dependency. With npm, you can use the overrides feature in your package.json to force the use of a specific version. For example:

    {
  "overrides": {
    "external-editor": {
      "tmp": "^0.2.4"
    }
  }
}

    This tells npm to use version 0.2.4 or later of the tmp library, regardless of what version external-editor specifies.

  4. Audit Your Dependencies: Use npm audit or yarn audit to identify vulnerabilities in your dependencies. These commands will check your project's dependencies against known vulnerability databases and provide recommendations for fixing them.

Best Practices for Dependency Management

  • Keep Dependencies Updated: Regularly update your dependencies to the latest versions to benefit from security patches and bug fixes.
  • Use Version Control: Use a version control system like Git to track changes to your package.json and package-lock.json or yarn.lock files. This allows you to easily revert changes if something goes wrong.
  • Monitor for Vulnerabilities: Use tools like Snyk or Dependabot to automatically monitor your dependencies for vulnerabilities and alert you when new issues are discovered.

Conclusion

While CVE-2025-54798 is a low-severity vulnerability, it’s a good reminder to stay vigilant about our dependencies and keep them updated. By understanding the dependency chain and using the right tools, we can effectively mitigate these risks and keep our applications secure. Remember, security is a continuous process, and every little bit helps!

Stay safe out there, and happy coding!