cbcvebase.
CVE-2020-11998
published 2020-09-10

CVE-2020-11998: A regression has been introduced in the commit preventing JMX re-bind. By passing an empty environment map to RMIConnectorServer, instead of the map that…

PriorityP275critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
51.23%
98.8th percentile
A regression has been introduced in the commit preventing JMX re-bind. By passing an empty environment map to RMIConnectorServer, instead of the map that contains the authentication credentials, it leaves ActiveMQ open to the following attack: https://docs.oracle.com/javase/8/docs/technotes/guides/management/agent.html "A remote client could create a javax.management.loading.MLet MBean and use it to create new MBeans from arbitrary URLs, at least if there is no security manager. In other words, a rogue remote client could make your Java application execute arbitrary code." Mitigation: Upgrade to Apache ActiveMQ 5.15.13

Affected

9 ranges
VendorProductVersion rangeFixed in
apacheactivemq
debianactivemq
oraclecommunications_diameter_signaling_router8.0.0 – 8.5.0
oraclecommunications_element_manager8.2.0 – 8.2.4.0
oraclecommunications_session_report_manager8.0.0 – 8.2.2
oraclecommunications_session_route_manager8.0.0 – 8.2.2
oracleenterprise_repository
oracleflexcube_private_banking
oracleflexcube_private_banking

Detection & IOCsextracted from sources · hover to see the quote

  • Detect attempts to create javax.management.loading.MLet MBeans via JMX, which can be used to load arbitrary code from remote URLs against an unauthenticated ActiveMQ JMX/RMI interface
  • Monitor for unauthenticated RMI/JMX connections to ActiveMQ — the vulnerability arises because RMIConnectorServer is started with an empty environment map (no credentials), leaving the JMX port open without authentication
  • Alert on remote code execution attempts via JMX MLet MBean instantiation from arbitrary URLs on Apache ActiveMQ versions prior to 5.15.13
  • ·The vulnerability only exists when no Java security manager is in place; environments with a properly configured security manager are less exposed
  • ·This is a regression bug — the empty environment map was introduced in a specific commit intended to prevent JMX re-bind; patching to Apache ActiveMQ 5.15.13 restores proper credential passing

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
osv9.8CRITICAL
vendor_debian9.8LOW
vendor_oracle9.8CRITICAL
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