---
id: CVE-2026-34151
title: XWiki Platform is a generic wiki platform
summary: >-
  XWiki Platform is a generic wiki platform. Prior to 17.10.5 and 18.2.0, the
  /skin/ action in com.xpn.xwiki.web.SkinAction can resolve double-encoded
  parent-directory segments outside the intended skin or web-application
  resource prefix w…
severity: high
cvss: 8.2
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-24
vendor: xwiki
product: xwiki-platform
affected:
  - xwiki-platform < 17.10.5
  - 'xwiki-platform >= 18.0.0-rc-1, < 18.2.0'
patched:
  - 'org.xwiki.platform:xwiki-platform-oldcore 17.10.5'
  - 'org.xwiki.platform:xwiki-platform-oldcore 18.2.0'
published: '2026-09-14'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T19:17:19.853'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-34151'
references:
  - url: 'https://github.com/xwiki/xwiki-commons/pull/1675'
    label: security-advisories@github.com
  - url: >-
      https://github.com/xwiki/xwiki-platform/commit/79eba8655f3a96021a8e7ad07956e48d20a82383
    label: security-advisories@github.com
  - url: >-
      https://github.com/xwiki/xwiki-platform/commit/f7b33704083d3b4e45d1b9fc1e2cc33c66855f85
    label: security-advisories@github.com
  - url: >-
      https://github.com/xwiki/xwiki-platform/releases/tag/xwiki-platform-17.10.5
    label: security-advisories@github.com
  - url: 'https://github.com/xwiki/xwiki-platform/releases/tag/xwiki-platform-18.2.0'
    label: security-advisories@github.com
  - url: >-
      https://github.com/xwiki/xwiki-platform/security/advisories/GHSA-qj4x-9g63-25g6
    label: security-advisories@github.com
  - url: 'https://jira.xwiki.org/browse/XCOMMONS-3594'
    label: security-advisories@github.com
  - url: 'https://jira.xwiki.org/browse/XWIKI-24075'
    label: security-advisories@github.com
  - url: 'https://github.com/advisories/GHSA-qj4x-9g63-25g6'
tags:
  - nvd
  - cve.org
  - ghsa
  - maven
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-14T18:56:04.582032Z'
cvssSource: cna
aliases:
  - GHSA-qj4x-9g63-25g6
ecosystem: maven
ingestedAt: '2026-07-07T13:53:11.868Z'
epss: 0.00542
epssPercentile: 0.44511
---

## Overview

XWiki Platform is a generic wiki platform. Prior to 17.10.5 and 18.2.0, the /skin/ action in com.xpn.xwiki.web.SkinAction can resolve double-encoded parent-directory segments outside the intended skin or web-application resource prefix when Jetty 12 or later decodes the request path. The affected lookup is replaced with Environment.getResourceAsStream(String, String), which constrains a resource to its expected prefix. An unauthenticated remote attacker can use the vulnerable behavior to read arbitrary resources permitted to the Jetty process, including WEB-INF/xwiki.cfg and, depending on deployment depth and operating-system permissions, host files. Tomcat and Jetty versions before 12 do not appear affected. This issue is fixed in versions 17.10.5 and 18.2.0.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-34151)

Affected packages:

- `org.xwiki.platform:xwiki-platform-oldcore < 17.10.5`
- `org.xwiki.platform:xwiki-platform-oldcore >= 18.0.0-rc-1, < 18.2.0`

Patched in:

- `org.xwiki.platform:xwiki-platform-oldcore 17.10.5`
- `org.xwiki.platform:xwiki-platform-oldcore 18.2.0`

Source: https://github.com/advisories/GHSA-qj4x-9g63-25g6