cbcvebase.
CVE-2021-28164
published 2021-04-01

CVE-2021-28164: In Eclipse Jetty 9.4.37.v20210219 to 9.4.38.v20210224, the default compliance mode allows requests with URIs that contain %2e or %2e%2e segments to access…

PriorityP265medium5.3CVSS 3.1
AVNACLPRNUINSUCLINAN
EXPLOIT
EPSS
82.37%
99.6th percentile
In Eclipse Jetty 9.4.37.v20210219 to 9.4.38.v20210224, the default compliance mode allows requests with URIs that contain %2e or %2e%2e segments to access protected resources within the WEB-INF directory. For example a request to /context/%2e/WEB-INF/web.xml can retrieve the web.xml file. This can reveal sensitive information regarding the implementation of a web application.

Affected

33 ranges· showing 25
VendorProductVersion rangeFixed in
debianjetty9< jetty9 9.4.39-3 (bookworm)jetty9 9.4.39-3 (bookworm)
debianjetty9< jetty9 9.4.39-1 (bookworm)jetty9 9.4.39-1 (bookworm)
eclipsejetty
eclipsejetty
eclipsejetty>= 10.0.1 < 10.0.610.0.6
eclipsejetty>= 11.0.1 < 11.0.611.0.6
eclipsejetty>= 9.4.37 < 9.4.439.4.43
netappe-series_santricity_os_controller11.0 – 11.70.1
netappstorage_replication_adapter_for_clustered_data_ontap>= 9.6
netappvasa_provider_for_clustered_data_ontap>= 9.6
netappvirtual_storage_console>= 9.6
oracleautovue_for_agile_product_lifecycle_management
oraclebanking_apis
oraclebanking_apis
oraclebanking_digital_experience
oraclebanking_digital_experience
oraclecommunications_cloud_native_core_binding_support_function
oraclecommunications_cloud_native_core_security_edge_protection_proxy
oraclecommunications_cloud_native_core_service_communication_proxy
oraclecommunications_cloud_native_core_unified_data_repository
oraclecommunications_diameter_signaling_router8.0.0.0 – 8.5.0.2
oraclecommunications_session_route_manager8.0.0 – 8.2.4
oraclefinancial_services_crime_and_compliance_management_studio
oraclefinancial_services_crime_and_compliance_management_studio
oraclerest_data_services< 22.1.122.1.1

Detection & IOCsextracted from sources · hover to see the quote

url/%2e/WEB-INF/web.xml
url/context/%2e/WEB-INF/web.xml
url/%2e/WEB-INF/web.xml
path/WEB-INF/web.xml
commandGET /%2e/WEB-INF/web.xml HTTP/1.1
  • Detect HTTP GET requests where the URI contains the encoded segment %2e or %2e%2e followed by /WEB-INF/ — this is the canonical exploit path for CVE-2021-28164.
  • A successful exploit response will contain both the XML web-app schema string 'java.sun.com' in the body and 'application/xml' in the Content-Type header with HTTP 200 — use these as confirmation matchers.
  • Baseline check: a direct request to /WEB-INF/web.xml should return non-200/non-404 (blocked); if the %2e-encoded variant returns 200 with XML content, the instance is vulnerable.
  • Shodan query 'cpe:"cpe:2.3:a:eclipse:jetty"' can be used to identify internet-exposed Jetty instances for targeted scanning.
  • ·The vulnerability is only present when Jetty is running in its DEFAULT compliance mode. Explicitly configuring a stricter URI compliance mode mitigates the issue.
  • ·Affected versions are strictly 9.4.37.v20210219 and 9.4.38.v20210224; versions outside this range are not affected by CVE-2021-28164 (a related but distinct issue, CVE-2021-34429, covers 9.4.37–9.4.42, 10.0.1–10.0.5, 11.0.1–11.0.5).

CVSS provenance

nvdv3.15.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:P/I:N/A:N
ghsa5.3MEDIUM
osv5.3MEDIUM
vulncheck5.3MEDIUM
vendor_debian5.3MEDIUM
vendor_oracle5.3MEDIUM
vendor_redhat5.3MEDIUM
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