cbcvebase.
CVE-2016-5386
published 2016-07-19

CVE-2016-5386: The net/http package in Go through 1.6 does not attempt to address RFC 3875 section 4.1.18 namespace conflicts and therefore does not protect CGI applications…

PriorityP350high8.1CVSS 3.1
AVNACHPRNUINSUCHIHAH
EPSS
5.22%
91.6th percentile
The net/http package in Go through 1.6 does not attempt to address RFC 3875 section 4.1.18 namespace conflicts and therefore does not protect CGI applications from the presence of untrusted client data in the HTTP_PROXY environment variable, which might allow remote attackers to redirect a CGI application's outbound HTTP traffic to an arbitrary proxy server via a crafted Proxy header in an HTTP request, aka an "httpoxy" issue.

Affected

11 ranges
VendorProductVersion rangeFixed in
fedoraprojectfedora
fedoraprojectfedora
golanggo
golanggo>= 1.0 < 1.6.31.6.3
msrcazl3_golang_1.23.7-1_on_azure_linux_3.0
msrcazl3_golang_1.23.9-1_on_azure_linux_3.0
msrcazl3_golang_1.24.3-1_on_azure_linux_3.0
oraclelinux
redhatenterprise_linux_server
redhatenterprise_linux_server_aus
redhatenterprise_linux_server_eus

Detection & IOCsextracted from sources · hover to see the quote

  • Detect exploitation attempts by inspecting incoming HTTP requests for the presence of a 'Proxy' header, which CGI implementations may translate into the HTTP_PROXY environment variable
  • Flag any CGI-spawned process where the HTTP_PROXY environment variable is set to an unexpected or external proxy address, indicating possible httpoxy exploitation
  • Monitor outbound HTTP/HTTPS traffic from CGI processes for unexpected proxy usage or connections to attacker-controlled proxy servers, which may indicate successful httpoxy exploitation
  • Vulnerable Go versions are 1.0 through 1.6.2 and 1.7rc1; flag use of these versions in CGI environments as high-risk
  • The fix is tracked at https://golang.org/cl/25010 and https://golang.org/issue/16405; use these references to verify patch application in Go net/http/cgi package
  • ·Go HTTP servers that do NOT invoke CGI scripts are not directly vulnerable; the HTTP_PROXY var is not set in the server process's environment or in subprocesses launched directly by os.exec
  • ·The vulnerability affects Go's net/http package only when used in a CGI environment; both $HTTP_PROXY and $http_proxy are honoured for outbound requests

CVSS provenance

nvdv3.18.1HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P
osv8.1HIGH
vendor_msrc8.1HIGH
vendor_redhat8.1HIGH
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