cbcvebase.
CVE-2016-5388
published 2016-07-19

CVE-2016-5388: Apache Tomcat 7.x through 7.0.70 and 8.x through 8.5.4, when the CGI Servlet is enabled, follows RFC 3875 section 4.1.18 and therefore does not protect…

PriorityP261high8.1CVSS 3.0
AVNACHPRNUINSUCHIHAH
EPSS
50.90%
98.8th percentile
Apache Tomcat 7.x through 7.0.70 and 8.x through 8.5.4, when the CGI Servlet is enabled, follows RFC 3875 section 4.1.18 and therefore does not protect applications from the presence of untrusted client data in the HTTP_PROXY environment variable, which might allow remote attackers to redirect an application's outbound HTTP traffic to an arbitrary proxy server via a crafted Proxy header in an HTTP request, aka an "httpoxy" issue. NOTE: the vendor states "A mitigation is planned for future releases of Tomcat, tracked as CVE-2016-5388"; in other words, this is not a CVE ID for a vulnerability.

Affected

19 ranges
VendorProductVersion rangeFixed in
apachetomcat6.0 – 6.0.45
apachetomcat7.0 – 7.0.70
apachetomcat8.0 – 8.5.4
debiantomcat9
hpsystem_management_homepage<= 7.5.5.0
oraclelinux
oraclelinux
redhatenterprise_linux_desktop
redhatenterprise_linux_desktop
redhatenterprise_linux_hpc_node
redhatenterprise_linux_hpc_node
redhatenterprise_linux_hpc_node_eus
redhatenterprise_linux_server
redhatenterprise_linux_server
redhatenterprise_linux_server_aus
redhatenterprise_linux_server_eus
redhatenterprise_linux_server_tus
redhatenterprise_linux_workstation
redhatenterprise_linux_workstation

Detection & IOCsextracted from sources · hover to see the quote

  • Attack is only possible when the CGI Servlet is enabled in Tomcat; scope detection to CGI-enabled deployments of Tomcat 7.x through 7.0.70 and 8.x through 8.5.4.
  • Monitor CGI script processes for unexpected HTTP_PROXY environment variable values set from inbound request headers, which may indicate traffic is being redirected to an attacker-controlled proxy.
  • ·The vulnerability only applies when the CGI Servlet is explicitly enabled in Tomcat; default installations without CGI Servlet enabled are not affected.
  • ·The root cause is RFC 3875 section 4.1.18 compliance — CGI implementations that map HTTP headers to environment variables (HTTP_PROXY from Proxy header) are inherently susceptible unless the Proxy header is explicitly blocked or sanitized.

CVSS provenance

nvdv3.08.1HIGHCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.05.1MEDIUMAV:N/AC:H/Au:N/C:P/I:P/A:P
ghsa8.1HIGH
osv8.1HIGH
vendor_debian8.1LOW
vendor_redhat8.1HIGH
vendor_ubuntu8.1HIGH
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