git-diff Library Flaw Lets Attackers Run Shell Commands with Node Privileges

Attackers who control the text input for a diff comparison can execute operating system commands. The flaw exists in the git-diff library, a tool used in Node.js environments to compare file contents. By crafting specific strings within the document being diffed, an adversary can trigger command execution. This runs with the same privileges as the underlying Node.js process. The issue is recorded under CVE-2026-110634 in the National Vulnerability Database.

In plain English

The library is designed to show differences between two text blocks. It processes these text blocks using the shelljs.exec module to generate the comparison output. The problem arises because the library does not sufficiently sanitize the input before passing it to that module. An attacker can embed special characters that the system interprets as instructions rather than plain text. This allows the attacker to run any command the Node.js application is permitted to run.

The background

The affected component is maintained by the developer known as danday74. The vulnerability is present in all versions of the git-diff package released before version 2.0.7. The National Vulnerability Database assigns a CVSS score of 9.3 to this flaw, categorizing it as critical. The weakness is classified under CWE-78, which covers improper neutralization of special elements used in an OS command. This aligns with other recent library vulnerabilities, such as the pypdftk issue RedTeam Monitor reported on 2026-10-14.

What changes now

Security teams must audit their Node.js projects for usage of the git-diff library. Any project relying on versions earlier than 2.0.7 is exposed to this command injection risk. Developers should check their dependency trees to identify where this library is imported. Applications that accept user-generated content or external data for diffing are at the highest risk. Monitoring logs for unexpected shell commands or unusual process activity is also recommended.

What made it possible

Command injection flaws typically arise when applications pass untrusted data directly to system shells without proper validation. This weakness allows attackers to elevate their access from a simple data entry point to full command execution. It serves as a primary initial access or privilege escalation vector during intrusions. Teams usually mitigate this by ensuring that all inputs are strictly validated before reaching system calls. Checking whether libraries handle special characters safely is a critical step in reducing exposure to such vulnerabilities.

What to do and how to stay safe: git-diff

• Review all Node.js projects to identify if the git-diff library is included in the dependencies.
• Verify the specific version of the library in use and compare it against the vulnerable range.
• Monitor application logs for any unexpected command execution or shell activity originating from diff operations.
• Prepare to update the library once the vendor provides a confirmed secure update for affected versions.

Step-by-step guide: Automatic Updates Mistakes That Leave Systems Exposed

General security guidance from the RedTeam Monitor newsroom. It is not confirmed advice from the organisations named in this story.

Frequently asked questions

What is the CVSS score for the git-diff command injection flaw?

The National Vulnerability Database rates CVE-2026-110634 as critical with a CVSS score of 9.3.

Which versions of the git-diff library are affected by this vulnerability?

All versions of the git-diff library before 2.0.7 contain this OS command injection vulnerability.

How do attackers exploit this specific flaw in the git-diff library?

Attackers supply crafted strings to the gitDiff API, embedding command substitutions that shelljs.exec evaluates.