Vulnerabilities > CVE-2017-7650 - Improper Authentication vulnerability in multiple products
Attack vector
NETWORK Attack complexity
LOW Privileges required
LOW Confidentiality impact
HIGH Integrity impact
NONE Availability impact
NONE Summary
In Mosquitto before 1.4.12, pattern based ACLs can be bypassed by clients that set their username/client id to '#' or '+'. This allows locally or remotely connected clients to access MQTT topics that they do have the rights to. The same issue may be present in third party authentication/access control plugins for Mosquitto.
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 Debian Local Security Checks NASL id DEBIAN_DLA-961.NASL description CVE-2017-7650: Pattern based ACLs can be bypassed by clients that set their username/client id to ‘#’ or ‘+’. This allows locally or remotely connected clients to access MQTT topics that they do have the rights to. The same issue may be present in third-party authentication/access control plugins for Mosquitto. The vulnerability only comes into effect where pattern based ACLs are in use, or potentially where third-party plugins are in use. For Debian 7 last seen 2020-03-17 modified 2017-05-31 plugin id 100513 published 2017-05-31 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/100513 title Debian DLA-961-1 : mosquitto security update code #%NASL_MIN_LEVEL 80502 # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from Debian Security Advisory DLA-961-1. The text # itself is copyright (C) Software in the Public Interest, Inc. # include("compat.inc"); if (description) { script_id(100513); script_version("3.7"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/03/12"); script_cve_id("CVE-2017-7650"); script_name(english:"Debian DLA-961-1 : mosquitto security update"); script_summary(english:"Checks dpkg output for the updated packages."); script_set_attribute( attribute:"synopsis", value:"The remote Debian host is missing a security update." ); script_set_attribute( attribute:"description", value: "CVE-2017-7650: Pattern based ACLs can be bypassed by clients that set their username/client id to ‘#’ or ‘+’. This allows locally or remotely connected clients to access MQTT topics that they do have the rights to. The same issue may be present in third-party authentication/access control plugins for Mosquitto. The vulnerability only comes into effect where pattern based ACLs are in use, or potentially where third-party plugins are in use. For Debian 7 'Wheezy', these problems have been fixed in version 0.15-2+deb7u1. We recommend that you upgrade your mosquitto packages. NOTE: Tenable Network Security has extracted the preceding description block directly from the DLA security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues." ); script_set_attribute( attribute:"see_also", value:"https://lists.debian.org/debian-lts-announce/2017/05/msg00034.html" ); script_set_attribute( attribute:"see_also", value:"https://packages.debian.org/source/wheezy/mosquitto" ); script_set_attribute(attribute:"solution", value:"Upgrade the affected packages."); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:P/I:N/A:N"); script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C"); script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N"); script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C"); script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available"); script_set_attribute(attribute:"exploit_available", value:"false"); script_set_attribute(attribute:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libmosquitto0"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libmosquitto0-dev"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libmosquittopp0"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libmosquittopp0-dev"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:mosquitto"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:mosquitto-clients"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python-mosquitto"); script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:7.0"); script_set_attribute(attribute:"patch_publication_date", value:"2017/05/30"); script_set_attribute(attribute:"plugin_publication_date", value:"2017/05/31"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof."); script_family(english:"Debian Local Security Checks"); script_dependencies("ssh_get_info.nasl"); script_require_keys("Host/local_checks_enabled", "Host/Debian/release", "Host/Debian/dpkg-l"); exit(0); } include("audit.inc"); include("debian_package.inc"); if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED); if (!get_kb_item("Host/Debian/release")) audit(AUDIT_OS_NOT, "Debian"); if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING); flag = 0; if (deb_check(release:"7.0", prefix:"libmosquitto0", reference:"0.15-2+deb7u1")) flag++; if (deb_check(release:"7.0", prefix:"libmosquitto0-dev", reference:"0.15-2+deb7u1")) flag++; if (deb_check(release:"7.0", prefix:"libmosquittopp0", reference:"0.15-2+deb7u1")) flag++; if (deb_check(release:"7.0", prefix:"libmosquittopp0-dev", reference:"0.15-2+deb7u1")) flag++; if (deb_check(release:"7.0", prefix:"mosquitto", reference:"0.15-2+deb7u1")) flag++; if (deb_check(release:"7.0", prefix:"mosquitto-clients", reference:"0.15-2+deb7u1")) flag++; if (deb_check(release:"7.0", prefix:"python-mosquitto", reference:"0.15-2+deb7u1")) flag++; if (flag) { if (report_verbosity > 0) security_warning(port:0, extra:deb_report_get()); else security_warning(0); exit(0); } else audit(AUDIT_HOST_NOT, "affected");
NASL family Fedora Local Security Checks NASL id FEDORA_2017-C2113AACD2.NASL description Fix CVE-2017-7650 (rhbz#1456507) 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 2017-06-12 plugin id 100734 published 2017-06-12 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/100734 title Fedora 25 : mosquitto (2017-c2113aacd2) code #%NASL_MIN_LEVEL 80502 # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from Fedora Security Advisory FEDORA-2017-c2113aacd2. # include("compat.inc"); if (description) { script_id(100734); script_version("3.5"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04"); script_cve_id("CVE-2017-7650"); script_xref(name:"FEDORA", value:"2017-c2113aacd2"); script_name(english:"Fedora 25 : mosquitto (2017-c2113aacd2)"); script_summary(english:"Checks rpm output for the updated package."); script_set_attribute( attribute:"synopsis", value:"The remote Fedora host is missing a security update." ); script_set_attribute( attribute:"description", value: "Fix CVE-2017-7650 (rhbz#1456507) 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." ); script_set_attribute( attribute:"see_also", value:"https://bodhi.fedoraproject.org/updates/FEDORA-2017-c2113aacd2" ); script_set_attribute( attribute:"solution", value:"Update the affected mosquitto package." ); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:P/I:N/A:N"); script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N"); script_set_attribute(attribute:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:mosquitto"); script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:25"); script_set_attribute(attribute:"vuln_publication_date", value:"2017/09/11"); script_set_attribute(attribute:"patch_publication_date", value:"2017/06/11"); script_set_attribute(attribute:"plugin_publication_date", value:"2017/06/12"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof."); script_family(english:"Fedora Local Security Checks"); script_dependencies("ssh_get_info.nasl"); script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list"); exit(0); } include("audit.inc"); include("global_settings.inc"); include("rpm.inc"); if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED); release = get_kb_item("Host/RedHat/release"); if (isnull(release) || "Fedora" >!< release) audit(AUDIT_OS_NOT, "Fedora"); os_ver = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:release); if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora"); os_ver = os_ver[1]; if (! preg(pattern:"^25([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 25", "Fedora " + os_ver); if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING); cpu = get_kb_item("Host/cpu"); if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH); if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu); flag = 0; if (rpm_check(release:"FC25", reference:"mosquitto-1.4.12-1.fc25")) flag++; if (flag) { security_report_v4( port : 0, severity : SECURITY_WARNING, extra : rpm_report_get() ); exit(0); } else { tested = pkg_tests_get(); if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested); else audit(AUDIT_PACKAGE_NOT_INSTALLED, "mosquitto"); }
NASL family Fedora Local Security Checks NASL id FEDORA_2017-59F85FEF2C.NASL description Fix CVE-2017-7650 (rhbz#1456507) 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 2017-07-17 plugin id 101636 published 2017-07-17 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/101636 title Fedora 26 : mosquitto (2017-59f85fef2c) NASL family Debian Local Security Checks NASL id DEBIAN_DSA-3865.NASL description It was discovered that pattern-based ACLs in the Mosquitto MQTT broker could be bypassed. last seen 2020-06-01 modified 2020-06-02 plugin id 100484 published 2017-05-30 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/100484 title Debian DSA-3865-1 : mosquitto - security update NASL family Fedora Local Security Checks NASL id FEDORA_2017-486A536B62.NASL description Fix CVE-2017-7650 (rhbz#1456507) 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 2017-06-13 plugin id 100742 published 2017-06-13 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/100742 title Fedora 24 : mosquitto (2017-486a536b62)