CVE-2026-33137: XWiki Platform has an Unauthenticated XAR Import via REST /wikis/{wikiName}

Critical severity · published May 20, 2026

CVE-2026-33137

XWiki Platform has an Unauthenticated XAR Import via REST /wikis/{wikiName}

9.3

CVSS

0.6%

EPSS

On KEV

Description

XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. XWiki Platform is a generic wiki platform. In versions starting with 15.10.6 and prior to 18.1.0-rc-1, 17.10.3, 17.4.9, and 16.10.17, the POST /wikis/{wikiName} API executes a XAR import without performing any authentication or authorization checks, allowing an unauthenticated attacker to create or update documents in the target wiki. This vulnerability has been patched in XWiki 16.10.17, 17.4.9, 17.10.3, 18.0.1 and 18.1.0-rc-1.

Exploitation

Is it being used?

Exploit prediction (EPSS)0.6% · higher than 48% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

xwiki-platform · xwiki

>= 15.10.6, < 16.10.17; >= 17.0.0-rc-1, < 17.4.9; >= 17.5.0, < 17.10.3; >= 18.0.0-rc-1, < 18.1.0-rc-1 · source: vendor

Affected product

xwiki-platform