8.7
HIGH CVSS 3.1
CVE-2026-43888
Outline: Zip Extraction Path Escape via PATH_MAX Truncation in Collection Import
Description

Outline is a service that allows for collaborative documentation. Prior to 1.7.0, ZipHelper.extract computes the extraction path for each entry by passing a full filesystem path through trimFileAndExt, a filename helper that calls path.basename on its input when truncating. When a zip entry's nested path is long enough to push the joined filesystem path over MAX_PATH_LENGTH (4096 bytes), trimFileAndExt silently drops all directory components and returns a bare filename. fs.createWriteStream then opens the file relative to the process working directory instead of inside the extraction sandbox, and the escaped file persists after import cleanup because cleanupExtractedData only removes the temporary extraction directory. This vulnerability is fixed in 1.7.0.

INFO

Published Date :

May 11, 2026, 10:22 p.m.

Last Modified :

May 11, 2026, 10:22 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-43888 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH MITRE-CVE
Solution
Update Outline to version 1.7.0 or later to fix the path traversal vulnerability.
  • Update Outline to version 1.7.0 or later.
  • Verify extraction paths are properly sanitized.
  • Ensure cleanup routines remove all temporary files.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-43888.

URL Resource
https://github.com/outline/outline/security/advisories/GHSA-hw32-2v7j-mgqc
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-43888 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-43888 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-43888 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    May. 11, 2026

    Action Type Old Value New Value
    Added Description Outline is a service that allows for collaborative documentation. Prior to 1.7.0, ZipHelper.extract computes the extraction path for each entry by passing a full filesystem path through trimFileAndExt, a filename helper that calls path.basename on its input when truncating. When a zip entry's nested path is long enough to push the joined filesystem path over MAX_PATH_LENGTH (4096 bytes), trimFileAndExt silently drops all directory components and returns a bare filename. fs.createWriteStream then opens the file relative to the process working directory instead of inside the extraction sandbox, and the escaped file persists after import cleanup because cleanupExtractedData only removes the temporary extraction directory. This vulnerability is fixed in 1.7.0.
    Added CVSS V3.1 AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:H
    Added CWE CWE-22
    Added Reference https://github.com/outline/outline/security/advisories/GHSA-hw32-2v7j-mgqc
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.