Vulnerabilities > CVE-2016-9646 - Improper Authentication vulnerability in multiple products
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
NONE Integrity impact
LOW Availability impact
NONE Summary
ikiwiki before 3.20161229 incorrectly called the CGI::FormBuilder->field method (similar to the CGI->param API that led to Bugzilla's CVE-2014-1572), which can be abused to lead to commit metadata forgery.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Authentication Abuse An attacker obtains unauthorized access to an application, service or device either through knowledge of the inherent weaknesses of an authentication mechanism, or by exploiting a flaw in the authentication scheme's implementation. In such an attack an authentication mechanism is functioning but a carefully controlled sequence of events causes the mechanism to grant access to the attacker. This attack may exploit assumptions made by the target's authentication procedures, such as assumptions regarding trust relationships or assumptions regarding the generation of secret values. This attack differs from Authentication Bypass attacks in that Authentication Abuse allows the attacker to be certified as a valid user through illegitimate means, while Authentication Bypass allows the user to access protected material without ever being certified as an authenticated user. This attack does not rely on prior sessions established by successfully authenticating users, as relied upon for the "Exploitation of Session Variables, Resource IDs and other Trusted Credentials" attack patterns.
- Exploiting Trust in Client (aka Make the Client Invisible) An attack of this type exploits a programs' vulnerabilities in client/server communication channel authentication and data integrity. It leverages the implicit trust a server places in the client, or more importantly, that which the server believes is the client. An attacker executes this type of attack by placing themselves in the communication channel between client and server such that communication directly to the server is possible where the server believes it is communicating only with a valid client. There are numerous variations of this type of attack.
- Utilizing REST's Trust in the System Resource to Register Man in the Middle This attack utilizes a REST(REpresentational State Transfer)-style applications' trust in the system resources and environment to place man in the middle once SSL is terminated. Rest applications premise is that they leverage existing infrastructure to deliver web services functionality. An example of this is a Rest application that uses HTTP Get methods and receives a HTTP response with an XML document. These Rest style web services are deployed on existing infrastructure such as Apache and IIS web servers with no SOAP stack required. Unfortunately from a security standpoint, there frequently is no interoperable identity security mechanism deployed, so Rest developers often fall back to SSL to deliver security. In large data centers, SSL is typically terminated at the edge of the network - at the firewall, load balancer, or router. Once the SSL is terminated the HTTP request is in the clear (unless developers have hashed or encrypted the values, but this is rare). The attacker can utilize a sniffer such as Wireshark to snapshot the credentials, such as username and password that are passed in the clear once SSL is terminated. Once the attacker gathers these credentials, they can submit requests to the web service provider just as authorized user do. There is not typically an authentication on the client side, beyond what is passed in the request itself so once this is compromised, then this is generally sufficient to compromise the service's authentication scheme.
- Man in the Middle Attack This type of attack targets the communication between two components (typically client and server). The attacker places himself in the communication channel between the two components. Whenever one component attempts to communicate with the other (data flow, authentication challenges, etc.), the data first goes to the attacker, who has the opportunity to observe or alter it, and it is then passed on to the other component as if it was never intercepted. This interposition is transparent leaving the two compromised components unaware of the potential corruption or leakage of their communications. The potential for Man-in-the-Middle attacks yields an implicit lack of trust in communication or identify between two components.
Nessus
NASL family FreeBSD Local Security Checks NASL id FREEBSD_PKG_5ED094A0015011E7AE1B002590263BF5.NASL description Mitre reports : ikiwiki 3.20161219 does not properly check if a revision changes the access permissions for a page on sites with the git and recentchanges plugins and the CGI interface enabled, which allows remote attackers to revert certain changes by leveraging permissions to change the page before the revision was made. When CGI::FormBuilder->field( last seen 2020-06-01 modified 2020-06-02 plugin id 97544 published 2017-03-06 reporter This script is Copyright (C) 2017-2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/97544 title FreeBSD : ikiwiki -- multiple vulnerabilities (5ed094a0-0150-11e7-ae1b-002590263bf5) code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from the FreeBSD VuXML database : # # Copyright 2003-2018 Jacques Vidrine and contributors # # Redistribution and use in source (VuXML) and 'compiled' forms (SGML, # HTML, PDF, PostScript, RTF and so forth) with or without modification, # are permitted provided that the following conditions are met: # 1. Redistributions of source code (VuXML) must retain the above # copyright notice, this list of conditions and the following # disclaimer as the first lines of this file unmodified. # 2. Redistributions in compiled form (transformed to other DTDs, # published online in any format, converted to PDF, PostScript, # RTF and other formats) must reproduce the above copyright # notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # # THIS DOCUMENTATION IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, # THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR # PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS # BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, # OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT # OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR # BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, # WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE # OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION, # EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # include("compat.inc"); if (description) { script_id(97544); script_version("3.2"); script_cvs_date("Date: 2018/11/10 11:49:46"); script_cve_id("CVE-2016-10026", "CVE-2016-9645", "CVE-2016-9646"); script_name(english:"FreeBSD : ikiwiki -- multiple vulnerabilities (5ed094a0-0150-11e7-ae1b-002590263bf5)"); script_summary(english:"Checks for updated package in pkg_info output"); script_set_attribute( attribute:"synopsis", value:"The remote FreeBSD host is missing a security-related update." ); script_set_attribute( attribute:"description", value: "Mitre reports : ikiwiki 3.20161219 does not properly check if a revision changes the access permissions for a page on sites with the git and recentchanges plugins and the CGI interface enabled, which allows remote attackers to revert certain changes by leveraging permissions to change the page before the revision was made. When CGI::FormBuilder->field('foo') is called in list context (and in particular in the arguments to a subroutine that takes named arguments), it can return zero or more values for foo from the CGI request, rather than the expected single value. This breaks the usual Perl parsing convention for named arguments, similar to CVE-2014-1572 in Bugzilla (which was caused by a similar API design issue in CGI.pm)." ); script_set_attribute( attribute:"see_also", value:"https://ikiwiki.info/security/#index46h2" ); script_set_attribute( attribute:"see_also", value:"https://ikiwiki.info/security/#index47h2" ); # https://vuxml.freebsd.org/freebsd/5ed094a0-0150-11e7-ae1b-002590263bf5.html script_set_attribute( attribute:"see_also", value:"http://www.nessus.org/u?39a51429" ); script_set_attribute(attribute:"solution", value:"Update the affected package."); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N"); script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"); script_set_attribute(attribute:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:ikiwiki"); script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd"); script_set_attribute(attribute:"vuln_publication_date", value:"2016/12/19"); script_set_attribute(attribute:"patch_publication_date", value:"2017/03/05"); script_set_attribute(attribute:"plugin_publication_date", value:"2017/03/06"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2017-2018 and is owned by Tenable, Inc. or an Affiliate thereof."); script_family(english:"FreeBSD Local Security Checks"); script_dependencies("ssh_get_info.nasl"); script_require_keys("Host/local_checks_enabled", "Host/FreeBSD/release", "Host/FreeBSD/pkg_info"); exit(0); } include("audit.inc"); include("freebsd_package.inc"); if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED); if (!get_kb_item("Host/FreeBSD/release")) audit(AUDIT_OS_NOT, "FreeBSD"); if (!get_kb_item("Host/FreeBSD/pkg_info")) audit(AUDIT_PACKAGE_LIST_MISSING); flag = 0; if (pkg_test(save_report:TRUE, pkg:"ikiwiki<3.20161229")) flag++; if (flag) { if (report_verbosity > 0) security_warning(port:0, extra:pkg_report_get()); else security_warning(0); exit(0); } else audit(AUDIT_HOST_NOT, "affected");NASL family FreeBSD Local Security Checks NASL id FREEBSD_PKG_7B35A77A015111E7AE1B002590263BF5.NASL description ikiwiki reports : The ikiwiki maintainers discovered further flaws similar to CVE-2016-9646 in the passwordauth plugin last seen 2020-06-01 modified 2020-06-02 plugin id 97546 published 2017-03-06 reporter This script is Copyright (C) 2017-2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/97546 title FreeBSD : ikiwiki -- authentication bypass vulnerability (7b35a77a-0151-11e7-ae1b-002590263bf5) code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from the FreeBSD VuXML database : # # Copyright 2003-2018 Jacques Vidrine and contributors # # Redistribution and use in source (VuXML) and 'compiled' forms (SGML, # HTML, PDF, PostScript, RTF and so forth) with or without modification, # are permitted provided that the following conditions are met: # 1. Redistributions of source code (VuXML) must retain the above # copyright notice, this list of conditions and the following # disclaimer as the first lines of this file unmodified. # 2. Redistributions in compiled form (transformed to other DTDs, # published online in any format, converted to PDF, PostScript, # RTF and other formats) must reproduce the above copyright # notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # # THIS DOCUMENTATION IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, # THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR # PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS # BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, # OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT # OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR # BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, # WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE # OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION, # EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # include("compat.inc"); if (description) { script_id(97546); script_version("3.4"); script_cvs_date("Date: 2018/11/10 11:49:46"); script_cve_id("CVE-2017-0356"); script_name(english:"FreeBSD : ikiwiki -- authentication bypass vulnerability (7b35a77a-0151-11e7-ae1b-002590263bf5)"); script_summary(english:"Checks for updated package in pkg_info output"); script_set_attribute( attribute:"synopsis", value:"The remote FreeBSD host is missing a security-related update." ); script_set_attribute( attribute:"description", value: "ikiwiki reports : The ikiwiki maintainers discovered further flaws similar to CVE-2016-9646 in the passwordauth plugin's use of CGI::FormBuilder, with a more serious impact : An attacker who can log in to a site with a password can log in as a different and potentially more privileged user. An attacker who can create a new account can set arbitrary fields in the user database for that account" ); script_set_attribute( attribute:"see_also", value:"https://ikiwiki.info/security/#index48h2" ); # https://vuxml.freebsd.org/freebsd/7b35a77a-0151-11e7-ae1b-002590263bf5.html script_set_attribute( attribute:"see_also", value:"http://www.nessus.org/u?eeab34e6" ); script_set_attribute(attribute:"solution", value:"Update the affected package."); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P"); script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"); script_set_attribute(attribute:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:ikiwiki"); script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd"); script_set_attribute(attribute:"vuln_publication_date", value:"2017/01/11"); script_set_attribute(attribute:"patch_publication_date", value:"2017/03/05"); script_set_attribute(attribute:"plugin_publication_date", value:"2017/03/06"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2017-2018 and is owned by Tenable, Inc. or an Affiliate thereof."); script_family(english:"FreeBSD Local Security Checks"); script_dependencies("ssh_get_info.nasl"); script_require_keys("Host/local_checks_enabled", "Host/FreeBSD/release", "Host/FreeBSD/pkg_info"); exit(0); } include("audit.inc"); include("freebsd_package.inc"); if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED); if (!get_kb_item("Host/FreeBSD/release")) audit(AUDIT_OS_NOT, "FreeBSD"); if (!get_kb_item("Host/FreeBSD/pkg_info")) audit(AUDIT_PACKAGE_LIST_MISSING); flag = 0; if (pkg_test(save_report:TRUE, pkg:"ikiwiki<3.20170111")) flag++; if (flag) { if (report_verbosity > 0) security_hole(port:0, extra:pkg_report_get()); else security_hole(0); exit(0); } else audit(AUDIT_HOST_NOT, "affected");NASL family Debian Local Security Checks NASL id DEBIAN_DLA-812.NASL description Several vulnerabilities have been found in ikiwiki, a wiki compiler : CVE-2016-9646 Commit metadata forgery CVE-2016-10026 Authorization bypass when reverting changes CVE-2017-0356 Authentication bypass via repeated parameters For Debian 7 last seen 2020-03-17 modified 2017-02-01 plugin id 96911 published 2017-02-01 reporter This script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/96911 title Debian DLA-812-1 : ikiwiki security update NASL family Debian Local Security Checks NASL id DEBIAN_DSA-3760.NASL description Multiple vulnerabilities have been found in the Ikiwiki wiki compiler : - CVE-2016-9646 Commit metadata forgery via CGI::FormBuilder context-dependent APIs - CVE-2016-10026 Editing restriction bypass for git revert - CVE-2017-0356 Authentication bypass via repeated parameters Additional details on these vulnerabilities can be found at https://ikiwiki.info/security/ last seen 2020-06-01 modified 2020-06-02 plugin id 96462 published 2017-01-13 reporter This script is Copyright (C) 2017-2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/96462 title Debian DSA-3760-1 : ikiwiki - security update NASL family Fedora Local Security Checks NASL id FEDORA_2017-8873EBDB43.NASL description Update to the latest stable version. See https://ikiwiki.info/news/ for the list of changes. Security fix for CVE-2016-10026, CVE-2016-9646, CVE-2017-0356. Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues. last seen 2020-06-05 modified 2017-01-31 plugin id 96895 published 2017-01-31 reporter This script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/96895 title Fedora 24 : ikiwiki (2017-8873ebdb43) NASL family Fedora Local Security Checks NASL id FEDORA_2017-C756D37779.NASL description Update to the latest stable version. See https://ikiwiki.info/news/ for the list of changes. Security fix for CVE-2016-10026, CVE-2016-9646, CVE-2017-0356. Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues. last seen 2020-06-05 modified 2017-01-30 plugin id 96848 published 2017-01-30 reporter This script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/96848 title Fedora 25 : ikiwiki (2017-c756d37779)