CVE-2026-54527
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedJupyterLab 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.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceA stored Cross-Site Scripting (XSS) vulnerability exists in the JupyterLab Git extension where the createHeader() method in PlainTextDiff.ts directly injects Git filenames into innerHTML when rendering rename diffs in the Git History view, allowing malicious filenames to execute arbitrary JavaScript in victim browsers.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data>= 0.30.1, < 0.54.0= 0.30.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- Low
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Identify JupyterLab Git extension versionRun 'jupyter labextension list' or check package.json in the lab environment to find the @jupyterlab/git extension versionAffected if The installed version is >= 0.30.0 and < 0.54.0, or equals exactly 0.30.0
-
Confirm Git extension is loadedVerify that the JupyterLab Git extension appears in 'jupyter labextension list' output as enabled/activeAffected if The extension is installed and active, making the vulnerable code path accessible
-
Check Git History view accessibilityIn JupyterLab, verify access to the Git extension sidebar and its History view feature for any repositoryAffected if The Git History view can be opened, which is required for the vulnerable createHeader() method to execute
-
Identify repositories with untrusted contributorsReview any Git repositories used in JupyterLab for presence of commits from untrusted sources or unusual filename patternsAffected if Repositories contain commits from untrusted contributors, which could contain malicious filenames that trigger the XSS
A user is affected if the JupyterLab Git extension version falls within 0.30.0 or >= 0.30.1 but < 0.54.0, and they have access to the Git History view for repositories that may contain untrusted Git filenames.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped0.54.0
Upgrade the JupyterLab Git extension to version 0.54.0 or later. Until upgrade is possible, avoid viewing commit history of repositories with untrusted contributors.
0.54.0
- Check current version of jupyterlab-git: run `pip show jupyterlab-git` or `jupyter labextension list`
- Upgrade jupyterlab-git to version 0.54.0 or later: run `pip install --upgrade jupyterlab-git>=0.54.0` or `conda install -c conda-forge jupyterlab-git>=0.54.0`
- Restart JupyterLab to ensure the patched extension is loaded
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation2.0 h
- Testing3.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,512.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-54527 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-54527 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data