cbcvebase.
CVE-2019-17571
published 2019-12-20

CVE-2019-17571: Included in Log4j 1.2 is a SocketServer class that is vulnerable to deserialization of untrusted data which can be exploited to remotely execute arbitrary code…

PriorityP276critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
66.48%
99.2th percentile
Included in Log4j 1.2 is a SocketServer class that is vulnerable to deserialization of untrusted data which can be exploited to remotely execute arbitrary code when combined with a deserialization gadget when listening to untrusted network traffic for log data. This affects Log4j versions up to 1.2 up to 1.2.17.

Affected

29 ranges· showing 25
VendorProductVersion rangeFixed in
apachebookkeeper< 4.14.34.14.3
apachelog4j<= 1.2.17
apache_software_foundationlog4j
canonicalubuntu_linux
debianapache-log4j1.2< apache-log4j1.2 1.2.17-9 (bookworm)apache-log4j1.2 1.2.17-9 (bookworm)
debiandebian_linux
debiandebian_linux
debiandebian_linux
netapponcommand_system_manager3.0 – 3.1.3
opensuseleap
oracleapplication_testing_suite
oraclecommunications_network_integrity7.3.2 – 7.3.6
oracleendeca_information_discovery_studio
oraclefinancial_services_lending_and_leasing
oraclefinancial_services_lending_and_leasing14.1.0 – 14.8.0
oraclemysql_enterprise_monitor<= 8.0.29
oracleprimavera_gateway16.2 – 16.2.11
oracleprimavera_gateway17.12.0 – 17.12.7
oraclerapid_planning
oraclerapid_planning
oracleretail_extract_transform_and_load
oracleretail_service_backbone
oracleretail_service_backbone
oracleretail_service_backbone
oracleweblogic_server

Detection & IOCsextracted from sources · hover to see the quote

processorg.apache.log4j.net.SocketServer
  • Monitor for Log4j 1.x SocketServer listening on network interfaces accepting inbound serialized Java objects (log events) over TCP/UDP — any such listener is exploitable via a crafted deserialization payload.
  • Detect use of SerializedLayout with SocketAppender in log4j configuration files (e.g., log4j-server.properties, log4j.xml, log4j.properties) — this combination is the vulnerable attack surface.
  • Flag any inbound TCP/UDP connections to a process running org.apache.log4j.net.SocketServer carrying Java serialized object magic bytes (0xACED0005) as a potential exploitation attempt.
  • Alert on log4j-server.properties or equivalent config containing 'SerializedLayout' — replace with JsonLayout as mitigation indicator.
  • ·CVE-2019-17571 affects Log4j 1.x (up to 1.2.17) only; Log4j 2.x carries the analogous flaw under CVE-2017-5645 (fixed in 2.8.2). Do not conflate the two CVEs in detection rules.
  • ·Red Hat Satellite 5 (nutch package) ships the affected log4j version but does NOT load SocketServer classes, so the vulnerable code path is unreachable — avoid false-positive alerting on that deployment.
  • ·Exploitation requires a deserialization gadget chain to be present on the classpath in addition to the vulnerable SocketServer; detections should account for the presence of known gadget libraries (e.g., commons-collections) alongside log4j 1.x.

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_debian9.8CRITICAL
vendor_oracle9.8CRITICAL
vendor_redhat9.8CRITICAL
vendor_ubuntu9.8CRITICAL
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