cbcvebase.
CVE-2020-26217
published 2020-11-16

CVE-2020-26217: XStream before version 1.4.14 is vulnerable to Remote Code Execution.The vulnerability may allow a remote attacker to run arbitrary shell commands only by…

PriorityP278high8.8CVSS 3.1
AVNACLPRLUINSUCHIHAH
EXPLOIT
EPSS
85.00%
99.7th percentile
XStream before version 1.4.14 is vulnerable to Remote Code Execution.The vulnerability may allow a remote attacker to run arbitrary shell commands only by manipulating the processed input stream. Only users who rely on blocklists are affected. Anyone using XStream's Security Framework allowlist is not affected. The linked advisory provides code workarounds for users who cannot upgrade. The issue is fixed in version 1.4.14.

Affected

38 ranges· showing 25
VendorProductVersion rangeFixed in
apacheactivemq< 5.15.145.15.14
apacheactivemq
atlassianbamboo_data_center
debiandebian_linux
debiandebian_linux
debianlibxstream-java< libxstream-java 1.4.14-1 (bookworm)libxstream-java 1.4.14-1 (bookworm)
oraclebanking_cash_management
oraclebanking_cash_management
oraclebanking_cash_management
oraclebanking_corporate_lending_process_management
oraclebanking_corporate_lending_process_management
oraclebanking_corporate_lending_process_management
oraclebanking_credit_facilities_process_management
oraclebanking_credit_facilities_process_management
oraclebanking_credit_facilities_process_management
oraclebanking_platform
oraclebanking_platform
oraclebanking_platform
oraclebanking_supply_chain_finance
oraclebanking_supply_chain_finance
oraclebanking_supply_chain_finance
oraclebanking_trade_finance_process_management
oraclebanking_trade_finance_process_management
oraclebanking_trade_finance_process_management
oraclebanking_virtual_account_management

Detection & IOCsextracted from sources · hover to see the quote

commandcurl http://{{interactsh-url}}
processjava.lang.ProcessBuilder
  • Exploit payload uses XML deserialization to invoke java.lang.ProcessBuilder via XStream; look for 'ProcessBuilder' and 'start' tokens in deserialized XML input streams.
  • Proof-of-concept exploit triggers an outbound HTTP request with 'User-Agent: curl' as a callback; monitor for unexpected outbound curl-based HTTP requests from JVM processes.
  • Only deployments relying on XStream blocklists (denylist) are affected; allowlist-based Security Framework configurations are not vulnerable.
  • The exploit abuses insecure XML deserialization; monitor for XML payloads referencing 'javax.imageio.ImageIO$ContainsFilter', 'java.beans.EventHandler', 'java.lang.ProcessBuilder', or 'java.lang.Void' class types in input streams.
  • ·OpenShift Container Platform jenkins packages are NOT affected due to JEP-200 and SECURITY-383 mitigations already in place.

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.09.3CRITICALAV:N/AC:M/Au:N/C:C/I:C/A:C
ghsa9.8CRITICAL
osv9.8CRITICAL
vendor_oracle8.8HIGH
vendor_redhat8.8HIGH
vendor_debian8.0HIGH
vendor_ubuntu8.0HIGH
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