XSS in Jupyter Jupyterlab-Git
CVE-2026-54527
JupyterLab Git is a Git extension for JupyterLab. From 0.30.0b3 before 0.54.0, the PlainTextDiff.ts createHeader() method passes Git filenames directly to innerHTML when rendering renamed files in commit history, allowing a crafted filename to execute JavaScript when a victim views the rename diff in the Git History tab. This issue is fixed in version 0.54.0.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.005 (42.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 42.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Jupyter Jupyterlab-Git — versions 0.30.0
- Jupyterlab Jupyterlab-Git — versions >= 0.30.0b3, < 0.54.0
Weakness classification (CWE)
References
- github.com/jupyterlab/jupyterlab-git/commit/c6d37b88f36aa59aee317930b95e427fb9d… (Patch)
- github.com/jupyterlab/jupyterlab-git/releases/tag/v0.54.0 (Release Notes)
- github.com/jupyterlab/jupyterlab-git/security/advisories/GHSA-f962-v9hr-pfg5 (Exploit, Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-54527?
- CVE-2026-54527 is a critical-severity vulnerability in Jupyter Jupyterlab-Git, classified under Cross-site Scripting. CVSS score: 9.0/10. Published 2026-07-08.
- How severe is CVE-2026-54527?
- Critical severity. CVSS v3 base score is 9.0 out of 10.