CVE-2023-45134: XWiki Platform XSS vulnerability from account in the create page form via template provider

Should you act?

Critical, preconditions apply

Severe if exploited, but exploitation needs conditions that may not apply to you. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
• EPSS 1.8%, percentile 79: FIRST’s model estimates a 1.8% chance of exploitation activity in the next 30 days, higher than 79% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Needs an account (low (any account)). Exposure depends on who can log in.
• Only applies if your dependency tree includes org.xwiki.platform:xwiki-platform-web-templates (Maven) < 14.10.12, fixed in 14.10.12; org.xwiki.platform:xwiki-platform-web-templates (Maven) >= 15.0-rc-1, < 15.5-rc-1, fixed in 15.5-rc-1; org.xwiki.platform:xwiki-web-standard (Maven) >= 2.4-milestone-2, < 3.1-milestone-1, fixed in 3.1-milestone-1; org.xwiki.platform:xwiki-platform-web (Maven) >= 3.1-milestone-1, < 13.4-rc-1, fixed in 13.4-rc-1. Check your lockfile, including transitive dependencies.

What it is

XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. org.xwiki.platform:xwiki-platform-web starting in version 3.1-milestone-1 and prior to 13.4-rc-1, org.xwiki.platform:xwiki-platform-web-templates prior to versions 14.10.2 and 15.5-rc-1, and org.xwiki.platform:xwiki-web-standard starting in version 2.4-milestone-2 and prior to version 3.1-milestone-1 are vulnerable to cross-site scripting. An attacker can create a template provider on any document that is part of the wiki (could be the attacker's user profile) that contains malicious code. This code is executed when this template provider is selected during document creation which can be triggered by sending the user to a URL. For the attacker, the only requirement is to have an account as by default the own user profile is editable. This allows an attacker to execute arbitrary actions with the rights of the user opening the malicious link. Depending on the rights of the user, this may allow remote code execution and full read and write access to the whole XWiki installation. This has been patched in org.xwiki.platform:xwiki-platform-web 13.4-rc-1, org.xwiki.platform:xwiki-platform-web-templates 14.10.2 and 15.5-rc-1, and org.xwiki.platform:xwiki-web-standard 3.1-milestone-1 by adding the appropriate escaping. The vulnerable template file createinline.vm is part of XWiki's WAR and can be patched by manually applying the changes from the fix.

From the GitHub advisory

Impact An attacker can create a template provider on any document that is part of the wiki (could be the attacker's user profile) that contains malicious code. This code is executed when this template provider is selected during document creation which can be triggered by sending the user to a URL. For the attacker, the only requirement is to have an account as by default the own user profile is editable. This allows an attacker to execute arbitrary actions with the rights of the user opening the malicious link. Depending on the rights of the user, this may allow remote code execution and full read and write access to the whole XWiki installation.

For reproduction, the following steps can be used: 1. As a simple user with no script right, edit the user profile with the object editor and add an object of type "Template Provider Class". Set the name to "My Template", set template to any page on the wiki. In "Creation Restrictions", enter /xwiki/bin/create/Main/WebHome?parent=&templateprovider=XWiki. &name=foo&spaceReference=Bar, where is the URL of your XWiki installation and is the username of the attacker.

If an alert is displayed, the installation is vulnerable.

Patches This has been patched in XWiki 14.10.12 and 15.5RC1 by adding the appropriate escaping.

Workarounds The vulnerable template file createinline.vm is part of XWiki's WAR and can be patched by manually applying the changes from the fix.

Weakness type: CWE-79.

Product: org.xwiki.platform:xwiki-platform-web-templates (Maven) · Assigned by: GitHub_M · Published: 2023-10-25

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: low (any account)
• User interaction: required (a user must click/open something)
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation poc, automatable no, technical impact total.
• FIRST EPSS (model of 2026-10-21): 1.83% probability of exploitation activity in the next 30 days; percentile 79.

Timeline

• 2023-10-25 — CVE record published by GitHub_M
• 2023-10-25 — GitHub-reviewed advisory GHSA-gr82-8fj2-ggc3 published (critical)
• 2024-09-10 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-gr82-8fj2-ggc3 github.com
2. CVE.org record CVE-2023-45134 cve.org
3. NVD entry CVE-2023-45134 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com
3. jira.xwiki.org jira.xwiki.org

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