Vulnerability · Published Jul 8, 2026 · Assigned by GitHub_M

CVE-2026-54528jupyterlab-git excluded_paths Case-Sensitivity Bypass Allows Reading Excluded Directories

High 7.1

In plain English

A high-severity security flaw in jupyterlab-git from jupyterlab. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 36% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.1High

Exploit odds (30 days)0.4%top 64.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

JupyterLab Git is a Git extension for JupyterLab. Prior to 0.54.0, jupyterlab-git uses fnmatch.fnmatchcase() in GitHandler.prepare() in jupyterlab_git/handlers.py to enforce excluded_paths, allowing an authenticated user on a case-insensitive filesystem to vary URL path casing and read excluded directories. This issue is fixed in version 0.54.0.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
PyPI	jupyterlab-git	0.54.0	GHSA-436q-jwfr-rm2h
PyPI	jupyterlab-git	0.54.0	PYSEC-2026-2539

Affected products (as reported)

Vendor	Product	Versions
jupyterlab	jupyterlab-git	< 0.54.0

Weakness: CWE-178 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N

References

https://github.com/jupyterlab/jupyterlab-git/security/advisories/GHSA-436q-jwfr-rm2h x_refsource_CONFIRM
https://github.com/jupyterlab/jupyterlab-git/commit/460035275b5963dc96e364e60ba6a73717fbd033 x_refsource_MISC
https://github.com/jupyterlab/jupyterlab-git/releases/tag/v0.54.0 x_refsource_MISC