Vulnerabilities
Misconfiguration
Compliance
CVE Vulnerabilities

CVE-2016-4975

Improper Neutralization of CRLF Sequences ('CRLF Injection')

Published: Aug 14, 2018 | Modified: Nov 21, 2024
CVSS 3.x
6.1
MEDIUM
Source:
NVD
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CVSS 2.x
4.3 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N
RedHat/V2
RedHat/V3
3.7 MODERATE
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Ubuntu
LOW
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2016-4975
CWEhttps://cwe.mitre.org/data/definitions/93.html

Possible CRLF injection allowing HTTP response splitting attacks for sites which use mod_userdir. This issue was mitigated by changes made in 2.4.25 and 2.2.32 which prohibit CR or LF injection into the Location or other outbound header key or value. Fixed in Apache HTTP Server 2.4.25 (Affected 2.4.1-2.4.23). Fixed in Apache HTTP Server 2.2.32 (Affected 2.2.0-2.2.31).

Weakness

The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs.

Affected Software

NameVendorStart VersionEnd Version
Http_serverApache2.2.0 (including)2.2.0 (including)
Http_serverApache2.2.2 (including)2.2.2 (including)
Http_serverApache2.2.3 (including)2.2.3 (including)
Http_serverApache2.2.4 (including)2.2.4 (including)
Http_serverApache2.2.6 (including)2.2.6 (including)
Http_serverApache2.2.8 (including)2.2.8 (including)
Http_serverApache2.2.9 (including)2.2.9 (including)
Http_serverApache2.2.10 (including)2.2.10 (including)
Http_serverApache2.2.11 (including)2.2.11 (including)
Http_serverApache2.2.12 (including)2.2.12 (including)
Http_serverApache2.2.13 (including)2.2.13 (including)
Http_serverApache2.2.14 (including)2.2.14 (including)
Http_serverApache2.2.15 (including)2.2.15 (including)
Http_serverApache2.2.16 (including)2.2.16 (including)
Http_serverApache2.2.17 (including)2.2.17 (including)
Http_serverApache2.2.18 (including)2.2.18 (including)
Http_serverApache2.2.19 (including)2.2.19 (including)
Http_serverApache2.2.20 (including)2.2.20 (including)
Http_serverApache2.2.21 (including)2.2.21 (including)
Http_serverApache2.2.22 (including)2.2.22 (including)
Http_serverApache2.2.23 (including)2.2.23 (including)
Http_serverApache2.2.24 (including)2.2.24 (including)
Http_serverApache2.2.25 (including)2.2.25 (including)
Http_serverApache2.2.26 (including)2.2.26 (including)
Http_serverApache2.2.27 (including)2.2.27 (including)
Http_serverApache2.2.29 (including)2.2.29 (including)
Http_serverApache2.2.31 (including)2.2.31 (including)
Http_serverApache2.4.1 (including)2.4.1 (including)
Http_serverApache2.4.2 (including)2.4.2 (including)
Http_serverApache2.4.3 (including)2.4.3 (including)
Http_serverApache2.4.4 (including)2.4.4 (including)
Http_serverApache2.4.6 (including)2.4.6 (including)
Http_serverApache2.4.7 (including)2.4.7 (including)
Http_serverApache2.4.9 (including)2.4.9 (including)
Http_serverApache2.4.10 (including)2.4.10 (including)
Http_serverApache2.4.12 (including)2.4.12 (including)
Http_serverApache2.4.16 (including)2.4.16 (including)
Http_serverApache2.4.17 (including)2.4.17 (including)
Http_serverApache2.4.18 (including)2.4.18 (including)
Http_serverApache2.4.20 (including)2.4.20 (including)
Http_serverApache2.4.23 (including)2.4.23 (including)
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-apache-commons-daemon-0:1.1.0-1.redhat_2.1.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-apache-commons-daemon-jsvc-1:1.1.0-1.redhat_2.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-apr-0:1.6.3-14.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-apr-util-0:1.6.1-9.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-httpd-0:2.4.29-17.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-mod_auth_kerb-0:5.4-36.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-mod_bmx-0:0.9.6-17.GA.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-mod_cluster-native-0:1.3.8-1.Final_redhat_2.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-mod_jk-0:1.2.43-1.redhat_1.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-mod_rt-0:2.4.1-19.GA.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-mod_security-0:2.9.1-23.GA.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-nghttp2-0:1.29.0-8.jbcs.el6*
JBoss Core Services on RHEL 6RedHatjbcs-httpd24-openssl-1:1.0.2n-11.jbcs.el6*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-apache-commons-daemon-0:1.1.0-1.redhat_2.1.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-apache-commons-daemon-jsvc-1:1.1.0-1.redhat_2.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-apr-0:1.6.3-14.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-apr-util-0:1.6.1-9.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-httpd-0:2.4.29-17.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-mod_auth_kerb-0:5.4-36.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-mod_bmx-0:0.9.6-17.GA.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-mod_cluster-native-0:1.3.8-1.Final_redhat_2.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-mod_jk-0:1.2.43-1.redhat_1.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-mod_rt-0:2.4.1-19.GA.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-mod_security-0:2.9.1-23.GA.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-nghttp2-0:1.29.0-8.jbcs.el7*
JBoss Core Services on RHEL 7RedHatjbcs-httpd24-openssl-1:1.0.2n-11.jbcs.el7*
Red Hat Enterprise Linux 7RedHathttpd-0:2.4.6-45.el7_3.4*
Text-Only JBCSRedHat*
Apache2Ubuntuesm-infra-legacy/trusty*
Apache2Ubuntuesm-infra/xenial*
Apache2Ubuntutrusty*
Apache2Ubuntutrusty/esm*
Apache2Ubuntuupstream*
Apache2Ubuntuxenial*

Potential Mitigations

References

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