cbcvebase.
CVE-2011-3556
published 2011-10-19

CVE-2011-3556: Unspecified vulnerability in the Java Runtime Environment component in Oracle Java SE JDK and JRE 7, 6 Update 27 and earlier, 5.0 Update 31 and earlier…

PriorityP179high7.5CVSS 2.0
AVNACLAuNCPIPAP
EXPLOIT
EPSS
76.24%
99.5th percentile
Unspecified vulnerability in the Java Runtime Environment component in Oracle Java SE JDK and JRE 7, 6 Update 27 and earlier, 5.0 Update 31 and earlier, 1.4.2_33 and earlier, and JRockit R28.1.4 and earlier allows remote attackers to affect confidentiality, integrity, and availability, related to RMI, a different vulnerability than CVE-2011-3557.

Affected

85 ranges· showing 25
VendorProductVersion rangeFixed in
oraclejrockit<= r28.1.4
oraclejrockit
oraclejrockit
oraclejrockit
oraclejrockit
oraclejrockit
oraclejrockit
sunjdk<= 1.6.0
sunjdk<= 1.5.0
sunjdk<= 1.4.2_33
sunjdk
sunjdk
sunjdk
sunjdk
sunjdk
sunjdk
sunjdk
sunjdk
sunjdk
sunjdk
sunjdk
sunjdk
sunjdk
sunjdk
sunjdk

Detection & IOCsextracted from sources · hover to see the quote

port1099
filenamermidummy.jar
pathmetasploit/RMILoader.class
pathmetasploit/RMIPayload.class
commandJRMI + [2,0x4b,0,0].pack("nCnN") + packet
bytes
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  • Detect Java RMI DGC exploit traffic by looking for the JRMI protocol header (bytes 4A 52 4D 49) followed by version 0x0002 and StreamType 0x4b on TCP port 1099
  • Detect Java serialization magic bytes (AC ED 00 05) within RMI DGC traffic on port 1099, indicating a serialized object being sent to the RMI endpoint
  • Alert on HTTP responses serving application/java-archive content-type from an RMI-related process, as the exploit causes the victim JVM to fetch and load a remote JAR payload over HTTP
  • The exploit targets the RMI Distributed Garbage Collector (DGC) endpoint available on every RMI service; monitor for unexpected outbound HTTP connections from Java processes listening on port 1099
  • The exploit does not work against JMX-only ports unless another RMI endpoint is co-located; scope RMI DGC detection to non-JMX RMI listeners
  • RMI method calls carry no authentication; any unauthenticated connection to a Java RMI registry port (default 1099) should be treated as potentially malicious in hardened environments
  • ·Exploitation requires the RMI Registry or RMI Activation service to be configured to allow loading classes from remote (HTTP) URLs — the default insecure configuration. Hardened deployments that restrict remote class loading are not exploitable.
  • ·The vulnerability affects Java SE JDK/JRE 7, 6 Update 27 and earlier, 5.0 Update 31 and earlier, 1.4.2_33 and earlier, and JRockit R28.1.4 and earlier; patched versions are not vulnerable.

CVSS provenance

nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
vendor_redhat7.5HIGH
vendor_ubuntu4.3MEDIUM
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