Cross-Site Scripting (XSS) in jupyterlab-git (CVE-2026-54527)
Summary
Cross-site scripting in jupyterlab-git (CVE-2026-54527). Successful exploitation can lead to full system takeover. Exploitable via POST /api/terminals. Mitigation: upgrade to 0.54.0 or later.
Original description
The description as published by the source.
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.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-54527 has been found in jupyterlab-git.
Attackers can target a specific entry point like POST /api/terminals over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 9.0/10.
What to do: upgrade jupyterlab-git to 0.54.0 or later.
If unsure, ask your IT team or search "jupyterlab-git CVE-2026-54527" on the vendor's site.
CVE-2026-54527 (jupyterlab-git) — CWE-79 / CVSS v3 9.0
Attack vector: remote (network-reachable)
Attack surface: POST /api/terminals
Patched: 0.54.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Cross-site scripting (XSS) (CWE-79) exists in jupyterlab-git. Attackers reach the vulnerable code path via POST /api/terminals.
Check the vendor advisory for the affected versions of jupyterlab-git. Attack surface: POST /api/terminals.
Severity: Critical (CVSS 9.0/10). Successful exploitation can lead to full system takeover.
Update to 0.54.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual POST /api/terminals requests with malformed payloads or SQL meta-characters. Run grep -r 'jupyterlab-git' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'jupyterlab-git' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
jupyterlab-gitを grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'POST /api/terminals' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /api/terminalsへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Apply patch patch
Upgrade jupyterlab-git to 0.54.0ステージング環境で 0.54.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスと、Step 2 で見つけた異常検知の続報チェックを含めること。
-
4Post-deployment verification verify
Replay attack against POST /api/terminals on staging to confirm patch closes the vectorパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番では Step 2 と同じログクエリでアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- patch github.com
- web github.com
- web github.com
- web github.com
- web pypi.org
- web pypi.org