@Jupyterlab/Git (Npm >= 0.30.0b3, < 0.54.0-A1)

A stored cross-site scripting (XSS) vulnerability, identified as CVE-2026-54527, in the `jupyterlab-git` JupyterLab extension (versions >= 0.30.0b3, < 0.54.0a1), specifically in `PlainTextDiff.ts`, allows an adversary with Git commit access to execute arbitrary JavaScript in a victim's browser and achieve Remote Code Execution (RCE) on the JupyterLab server by crafting a malicious filename in a Git commit that, when viewed as a rename diff, triggers the XSS payload to steal `_xsrf` cookies, open a terminal, and execute arbitrary shell commands to exfiltrate data.