CVE-2026-33137: Xwiki platform rest server XWiki Platform Has An Unauthenticated Vulnerability

CRITICAL
Advisory Identifier: GHSA-qrvh-r3f2-9h4r
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CWE-862
Published
Advisory Summary

CVE-2026-33137 is a CRITICAL xwiki platform has an unauthenticated vulnerability (CWE-862: Missing Authorization) affecting Xwiki platform rest server libraries in the Maven ecosystem. The issue involves xwiki platform has an unauthenticated xar import via rest /wikis/{wikiname}. Remediation is available by upgrading affected packages to version 16.10.17, 17.4.9, 17.10.3, 18.1.0-rc-1.

CVE-2026-33137 at a Glance

CVE Identifier CVE-2026-33137
GHSA Identifier GHSA-qrvh-r3f2-9h4r
Severity CRITICAL
CVSS v3.1 Base Score N/A
CWE Classification CWE-862: Missing Authorization
Affected Product Xwiki platform rest server
Package Ecosystem Maven
Published Date
Last Updated

How to Fix CVE-2026-33137

To remediate this vulnerability, upgrade all affected Xwiki platform rest server dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

org.xwiki.platform:xwiki-platform-rest-server fixed: 16.10.17 
<dependency>
    <groupId>org.xwiki.platform</groupId>
    <artifactId>xwiki-platform-rest-server</artifactId>
    <version>16.10.17</version>
</dependency>
org.xwiki.platform:xwiki-platform-rest-server fixed: 17.4.9 
<dependency>
    <groupId>org.xwiki.platform</groupId>
    <artifactId>xwiki-platform-rest-server</artifactId>
    <version>17.4.9</version>
</dependency>
org.xwiki.platform:xwiki-platform-rest-server fixed: 17.10.3 
<dependency>
    <groupId>org.xwiki.platform</groupId>
    <artifactId>xwiki-platform-rest-server</artifactId>
    <version>17.10.3</version>
</dependency>
org.xwiki.platform:xwiki-platform-rest-server fixed: 18.1.0-rc-1 
<dependency>
    <groupId>org.xwiki.platform</groupId>
    <artifactId>xwiki-platform-rest-server</artifactId>
    <version>18.1.0-rc-1</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree -Dincludes=org.xwiki.platform

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-33137, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.xwiki.platform

Analyze the terminal output to locate any version of Xwiki platform rest server in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 16.10.17), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.xwiki.platform command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-862: Missing Authorization, where the product does not perform an authorization check when an actor attempts to access a resource or perform an action. In Xwiki platform rest server, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact `POST /wikis/{wikiName}` executes a XAR import without performing any authentication or authorization checks, allowing an unauthenticated attacker to create or update documents in the target wiki ### Patches 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. ### Workarounds XWiki is not aware of any workarounds other than adding a rule into an HTTP proxy to prevent access POST request in the `/wikis/{wikiName}[/]` endpoint. ### Resources * https://jira.xwiki.org/browse/XWIKI-23953 * https://github.com/xwiki/xwiki-platform/commit/4b7b95b79256374d487e9ece1dc48f527966990f ### For more information If there are any questions or comments about this advisory: * Open an issue in [Jira XWiki.org](https://jira.xwiki.org/) * Send an email to the [Security Mailing List](mailto:security@xwiki.org) ### Attribution Reported by Sho Odagiri (GMO Cybersecurity by Ierae, Inc.).

CVE-2026-33137 Affected Xwiki platform rest server Versions

4 component(s)
Fixed Versions:
16.10.1717.4.917.10.318.1.0-rc-1
Product / Package Ecosystem Affected Versions Fixed Version
org.xwiki.platform:xwiki-platform-rest-server
maven/org.xwiki.platform/xwiki-platform-rest-server
Maven
≥ 15.10.6
< 16.10.17
16.10.17
org.xwiki.platform:xwiki-platform-rest-server
maven/org.xwiki.platform/xwiki-platform-rest-server
Maven
≥ 17.0.0-rc-1
< 17.4.9
17.4.9
org.xwiki.platform:xwiki-platform-rest-server
maven/org.xwiki.platform/xwiki-platform-rest-server
Maven
≥ 17.5.0
< 17.10.3
17.10.3
org.xwiki.platform:xwiki-platform-rest-server
maven/org.xwiki.platform/xwiki-platform-rest-server
Maven
≥ 18.0.0-rc-1
< 18.1.0-rc-1
18.1.0-rc-1

References

GitHub Advisory / Wiki ADVISORY
https://github.com/xwiki/xwiki-platform/security/advisories/GHSA-qrvh-r3f2-9h4r
NVD — CVE-2026-33137 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33137
Security Fix Commit FIX COMMIT
https://github.com/xwiki/xwiki-platform/commit/4b7b95b79256374d487e9ece1dc48f527966990f
Xwiki platform rest server Source Repository REPOSITORY
https://github.com/xwiki/xwiki-platform
jira.xwiki.org/browse/xwiki-23953 WEB
https://jira.xwiki.org/browse/XWIKI-23953

Frequently Asked Questions

What is CVE-2026-33137?
CVE-2026-33137 is a security vulnerability in Xwiki platform rest server involving XWiki Platform has an Unauthenticated XAR Import via REST /wikis/{wikiName} under CWE-862: Missing Authorization.
Which Xwiki platform rest server versions are affected?
Affected versions include releases prior to 16.10.17, 17.4.9, 17.10.3, 18.1.0-rc-1 across affected packages: org.xwiki.platform:xwiki-platform-rest-server.
What version fixes CVE-2026-33137?
Upgrading to 16.10.17, 17.4.9, 17.10.3, 18.1.0-rc-1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is xwiki-platform-rest-server affected?
Yes, org.xwiki.platform:xwiki-platform-rest-server is affected in releases prior to 16.10.17, 17.4.9, 17.10.3, 18.1.0-rc-1. Upgrade your dependency to 16.10.17, 17.4.9, 17.10.3, 18.1.0-rc-1 or later.
What CWE is associated with CVE-2026-33137?
CVE-2026-33137 is classified under CWE-862: Missing Authorization (The product does not perform an authorization check when an actor attempts to access a resource or perform an action.).
How can I check Maven dependencies for CVE-2026-33137?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.xwiki.platform'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-qrvh-r3f2-9h4r",
  "modified" : "2026-05-26T18:58:19Z",
  "published" : "2026-05-26T18:58:19Z",
  "aliases" : [ "CVE-2026-33137" ],
  "summary" : "XWiki Platform has an Unauthenticated XAR Import via REST /wikis/{wikiName}",
  "details" : "### Impact\n\n`POST /wikis/{wikiName}` executes a XAR import without performing any authentication or authorization checks, allowing an unauthenticated attacker to create or update documents in the target wiki\n\n### Patches\n\nThis vulnerability has been patched in XWiki 16.10.17, 17.4.9, 17.10.3, 18.0.1 and 18.1.0-rc-1.\n\n### Workarounds\n\nXWiki is not aware of any workarounds other than adding a rule into an HTTP proxy to prevent access POST request in the `/wikis/{wikiName}[/]` endpoint.\n\n### Resources\n\n* https://jira.xwiki.org/browse/XWIKI-23953\n* https://github.com/xwiki/xwiki-platform/commit/4b7b95b79256374d487e9ece1dc48f527966990f\n\n### For more information\n\nIf there are any questions or comments about this advisory:\n* Open an issue in [Jira XWiki.org](https://jira.xwiki.org/)\n* Send an email to the [Security Mailing List](mailto:security@xwiki.org)\n\n### Attribution\n\nReported by Sho Odagiri (GMO Cybersecurity by Ierae, Inc.).",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.xwiki.platform:xwiki-platform-rest-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "15.10.6"
      }, {
        "fixed" : "16.10.17"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.xwiki.platform:xwiki-platform-rest-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "17.0.0-rc-1"
      }, {
        "fixed" : "17.4.9"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.xwiki.platform:xwiki-platform-rest-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "17.5.0"
      }, {
        "fixed" : "17.10.3"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.xwiki.platform:xwiki-platform-rest-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "18.0.0-rc-1"
      }, {
        "fixed" : "18.1.0-rc-1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/xwiki/xwiki-platform/security/advisories/GHSA-qrvh-r3f2-9h4r"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-33137"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/xwiki/xwiki-platform/commit/4b7b95b79256374d487e9ece1dc48f527966990f"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/xwiki/xwiki-platform"
  }, {
    "type" : "WEB",
    "url" : "https://jira.xwiki.org/browse/XWIKI-23953"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-862" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-26T18:58:19Z",
    "nvd_published_at" : "2026-05-20T20:16:37Z"
  }
}