What’s Vulnerable › Vulnerabilities

CVE-2026-34151: XWiki Platform: Resource path traversal via /skin/ action endpoint in Jetty 12+

• Severity: high (CVSS 8.2 v4.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.5% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-09-14 · updated 2026-09-30
• Weakness: CWE-24

Description

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.

Affected products

• xwiki-platform: before 17.10.5; from 18.0.0-rc-1, < 18.2.0

References

• https://github.com/xwiki/xwiki-commons/pull/1675
• https://github.com/xwiki/xwiki-platform/commit/79eba8655f3a96021a8e7ad07956e48d20a82383
• https://github.com/xwiki/xwiki-platform/commit/f7b33704083d3b4e45d1b9fc1e2cc33c66855f85
• https://github.com/xwiki/xwiki-platform/releases/tag/xwiki-platform-17.10.5
• https://github.com/xwiki/xwiki-platform/releases/tag/xwiki-platform-18.2.0
• https://github.com/xwiki/xwiki-platform/security/advisories/GHSA-qj4x-9g63-25g6
• https://jira.xwiki.org/browse/XCOMMONS-3594
• https://jira.xwiki.org/browse/XWIKI-24075

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