CVE-2026-54527: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in jupyterlab jupyterlab-git
A critical cross-site scripting (XSS) vulnerability exists in jupyterlab-git versions before 0.54.0. The vulnerability arises because the createHeader() method in PlainTextDiff.ts passes Git filenames directly to innerHTML when rendering renamed files in the commit history. This allows an attacker to craft a malicious filename that executes JavaScript when viewed in the Git History tab. The issue is fixed in version 0.54.0.
AI Analysis
Technical Summary
CVE-2026-54527 is a CWE-79 cross-site scripting vulnerability in the jupyterlab-git extension for JupyterLab. Specifically, in versions from 0.30.0b3 up to but not including 0.54.0, the createHeader() method in PlainTextDiff.ts injects Git filenames directly into innerHTML without proper sanitization. This enables execution of arbitrary JavaScript code when a user views the rename diff in the Git History tab. The vulnerability is resolved in version 0.54.0.
Potential Impact
An attacker can exploit this vulnerability by crafting a malicious Git filename that, when rendered in the Git History tab, executes arbitrary JavaScript in the context of the victim's browser. This can lead to theft of sensitive information, session hijacking, or other malicious actions within the user's session. The CVSS 4.0 base score is 9.3 (critical), reflecting network attack vector, low attack complexity, no privileges required, user interaction required, and high impacts on confidentiality, integrity, availability, and security scope.
Mitigation Recommendations
Upgrade jupyterlab-git to version 0.54.0 or later, where this vulnerability is fixed. No other mitigations are specified. Patch status is confirmed fixed in 0.54.0.
CVE-2026-54527: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in jupyterlab jupyterlab-git
Description
A critical cross-site scripting (XSS) vulnerability exists in jupyterlab-git versions before 0.54.0. The vulnerability arises because the createHeader() method in PlainTextDiff.ts passes Git filenames directly to innerHTML when rendering renamed files in the commit history. This allows an attacker to craft a malicious filename that executes JavaScript when viewed in the Git History tab. The issue is fixed in version 0.54.0.
CVSS v4.0
Score 9.3critical
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-54527 is a CWE-79 cross-site scripting vulnerability in the jupyterlab-git extension for JupyterLab. Specifically, in versions from 0.30.0b3 up to but not including 0.54.0, the createHeader() method in PlainTextDiff.ts injects Git filenames directly into innerHTML without proper sanitization. This enables execution of arbitrary JavaScript code when a user views the rename diff in the Git History tab. The vulnerability is resolved in version 0.54.0.
Potential Impact
An attacker can exploit this vulnerability by crafting a malicious Git filename that, when rendered in the Git History tab, executes arbitrary JavaScript in the context of the victim's browser. This can lead to theft of sensitive information, session hijacking, or other malicious actions within the user's session. The CVSS 4.0 base score is 9.3 (critical), reflecting network attack vector, low attack complexity, no privileges required, user interaction required, and high impacts on confidentiality, integrity, availability, and security scope.
Mitigation Recommendations
Upgrade jupyterlab-git to version 0.54.0 or later, where this vulnerability is fixed. No other mitigations are specified. Patch status is confirmed fixed in 0.54.0.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-15T18:40:01.651Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a4ebdf5c9d9e3dbe3bf8b00
Added to database: 07/08/2026, 21:15:33 UTC
Last enriched: 07/08/2026, 21:28:32 UTC
Last updated: 07/09/2026, 03:27:39 UTC
Views: 26
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