CVE-2026-34151: XWiki Platform path traversal in skin action endpoint

CVE-2026-34151 · Severity: high · CVSS 4 · Published 2026-09-14

XWiki is an open-source enterprise wiki platform. A security vulnerability in how it handles certain web requests when running on Jetty 12+ allows unauthorized users to access sensitive files on the server. This could lead to the exposure of system passwords or internal configuration files, potentially compromising the entire server or the application's data.

Technologies: org.xwiki.platform:xwiki-platform-oldcore (Maven). Vendors: Maven, Xwiki.

Quick answers

Is CVE-2026-34151 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-34151 being exploited in the wild.
How severe is CVE-2026-34151?
High severity, with a CVSS score of 4, published 14 September 2026.
Which products and versions are affected?
org.xwiki.platform:xwiki-platform-oldcore (Maven) ECOSYSTEM:introduced=0,fixed=17.10.5; XWiki Platform Old Core < 17.10.5, >= 18.0.0-rc-1, < 18.2.0.
Is there a fix for CVE-2026-34151?
Yes. org.xwiki.platform:xwiki-platform-oldcore (Maven): upgrade to 17.10.5 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-34151 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-34151?
Check whether you run org.xwiki.platform:xwiki-platform-oldcore (Maven) or XWiki Platform Old Core at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • org.xwiki.platform:xwiki-platform-oldcore (Maven): upgrade to 17.10.5 or later
    # set org.xwiki.platform:xwiki-platform-oldcore to 17.10.5 in your pom.xml or build.gradle

Technical details

A path traversal vulnerability exists in XWiki Platform's 'Old Core' component when deployed on Jetty 12 or newer. The vulnerability is located in the '/skin/' action endpoint, where insufficient validation of the resource path allows an attacker to use double-encoded traversal sequences (e.g., '..%252f') to escape the intended directory. This can be exploited by a remote, unauthenticated attacker via a specially crafted URL to read any file the Jetty process has permissions to access, including sensitive system files like '/etc/passwd' or XWiki configuration files like 'xwiki.cfg'. The issue is patched in versions 17.10.5 and 18.2.0; users on older versions can mitigate the risk by using Tomcat or Jetty versions prior to 12.

Affected products

  • XWiki XWiki Platform Old Core < 17.10.5, >= 18.0.0-rc-1, < 18.2.0

Identifiers

  • CVE-2026-34151
  • GHSA-qj4x-9g63-25g6

Timeline

  • 2026-07-06: disclosed
  • 2026-07-07: advisory

References

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