Summary
XWiki Platform Stored Cross-site Scripting in the user profile via the timezone displayer
Workarounds
If you want to fix this problem on older versions of XWiki that have not been patched then you need to edit displayer_timezone.vm and escape the displayed time zone value here:
- $!value
+ $!escapetool.xml($value)
References
- JIRA issue https://jira.xwiki.org/browse/XWIKI-20276
- Fix https://github.com/xwiki/xwiki-platform/commit/d11ca5d781f8a42a85bc98eb82306c1431e764d4
For more information
If you have any questions or comments about this advisory:
- Open an issue in Jira XWiki.org
- Email us at Security Mailing List
Attribution
This vulnerability has been found and reported by @michitux .
Impact
Any registered user can exploit a stored XSS through their user profile by setting the payload as the value of the time zone user preference. Even though the time zone is selected from a drop down (no free text value) it can still be set from JavaScript (using the browser developer tools) or by calling the save URL on the user profile with the right query string. Once the time zone is set it is displayed without escaping which means the payload gets executed for any user that visits the malicious user profile, allowing the attacker to steal information and even gain more access rights (escalation to programming rights).
The problem is present since version 4.1M2 when the time zone user preference was introduced.
Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.
CVE-2023-40176 has a CVSS score of 5.4 (Medium). The vector is network-reachable, low privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (14.10.5); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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The issue has been fixed in XWiki 14.10.5 and 15.1RC1 by https://github.com/xwiki/xwiki-platform/commit/d11ca5d781f8a42a85bc98eb82306c1431e764d4 . The main fix is in the displayer_timezone.vm precisely at this line:
$!escapetool.xml($value)
By escaping the displayed time zone value we make sure the attacker's payload is not executed.
Frequently Asked Questions
- What is CVE-2023-40176? CVE-2023-40176 is a medium-severity cross-site scripting (XSS) vulnerability in org.xwiki.platform:xwiki-platform-web-templates (maven), affecting versions >= 4.1-milestone-2, < 14.10.5. It is fixed in 14.10.5. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
- How severe is CVE-2023-40176? CVE-2023-40176 has a CVSS score of 5.4 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of org.xwiki.platform:xwiki-platform-web-templates are affected by CVE-2023-40176? org.xwiki.platform:xwiki-platform-web-templates (maven) versions >= 4.1-milestone-2, < 14.10.5 is affected.
- Is there a fix for CVE-2023-40176? Yes. CVE-2023-40176 is fixed in 14.10.5. Upgrade to this version or later.
- Is CVE-2023-40176 exploitable, and should I be worried? Whether CVE-2023-40176 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2023-40176 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2023-40176? Upgrade
org.xwiki.platform:xwiki-platform-web-templatesto 14.10.5 or later.