Vulnerabilities > CVE-2017-7651 - Resource Exhaustion vulnerability in multiple products
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
NONE Integrity impact
NONE Availability impact
PARTIAL Summary
In Eclipse Mosquitto 1.4.14, a user can shutdown the Mosquitto server simply by filling the RAM memory with a lot of connections with large payload. This can be done without authentications if occur in connection phase of MQTT protocol.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- XML Ping of the Death An attacker initiates a resource depletion attack where a large number of small XML messages are delivered at a sufficiently rapid rate to cause a denial of service or crash of the target. Transactions such as repetitive SOAP transactions can deplete resources faster than a simple flooding attack because of the additional resources used by the SOAP protocol and the resources necessary to process SOAP messages. The transactions used are immaterial as long as they cause resource utilization on the target. In other words, this is a normal flooding attack augmented by using messages that will require extra processing on the target.
- XML Entity Expansion An attacker submits an XML document to a target application where the XML document uses nested entity expansion to produce an excessively large output XML. XML allows the definition of macro-like structures that can be used to simplify the creation of complex structures. However, this capability can be abused to create excessive demands on a processor's CPU and memory. A small number of nested expansions can result in an exponential growth in demands on memory.
- Inducing Account Lockout An attacker leverages the security functionality of the system aimed at thwarting potential attacks to launch a denial of service attack against a legitimate system user. Many systems, for instance, implement a password throttling mechanism that locks an account after a certain number of incorrect log in attempts. An attacker can leverage this throttling mechanism to lock a legitimate user out of their own account. The weakness that is being leveraged by an attacker is the very security feature that has been put in place to counteract attacks.
- Violating Implicit Assumptions Regarding XML Content (aka XML Denial of Service (XDoS)) XML Denial of Service (XDoS) can be applied to any technology that utilizes XML data. This is, of course, most distributed systems technology including Java, .Net, databases, and so on. XDoS is most closely associated with web services, SOAP, and Rest, because remote service requesters can post malicious XML payloads to the service provider designed to exhaust the service provider's memory, CPU, and/or disk space. The main weakness in XDoS is that the service provider generally must inspect, parse, and validate the XML messages to determine routing, workflow, security considerations, and so on. It is exactly these inspection, parsing, and validation routines that XDoS targets. There are three primary attack vectors that XDoS can navigate Target CPU through recursion: attacker creates a recursive payload and sends to service provider Target memory through jumbo payloads: service provider uses DOM to parse XML. DOM creates in memory representation of XML document, but when document is very large (for example, north of 1 Gb) service provider host may exhaust memory trying to build memory objects. XML Ping of death: attack service provider with numerous small files that clog the system. All of the above attacks exploit the loosely coupled nature of web services, where the service provider has little to no control over the service requester and any messages the service requester sends.
Nessus
NASL family Fedora Local Security Checks NASL id FEDORA_2018-D305559481.NASL description Fix CVE-2017-7651 (rhbz#1551755, rhbz#1551754) 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 2019-01-03 plugin id 120818 published 2019-01-03 reporter This script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/120818 title Fedora 28 : mosquitto (2018-d305559481) 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-2018-d305559481. # include("compat.inc"); if (description) { script_id(120818); script_version("1.4"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04"); script_cve_id("CVE-2017-7651", "CVE-2017-7652"); script_xref(name:"FEDORA", value:"2018-d305559481"); script_name(english:"Fedora 28 : mosquitto (2018-d305559481)"); 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-2017-7651 (rhbz#1551755, rhbz#1551754) 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-2018-d305559481" ); script_set_attribute( attribute:"solution", value:"Update the affected mosquitto package." ); script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:S/C:P/I:P/A:P"); script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C"); script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H"); script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C"); script_set_attribute(attribute:"cvss_score_source", value:"CVE-2017-7652"); script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available"); 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:28"); script_set_attribute(attribute:"vuln_publication_date", value:"2018/04/24"); script_set_attribute(attribute:"patch_publication_date", value:"2018/04/02"); script_set_attribute(attribute:"plugin_publication_date", value:"2019/01/03"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2019-2020 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:"^28([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 28", "Fedora " + os_ver); if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING); cpu = get_kb_item("Host/cpu"); if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH); if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu); flag = 0; if (rpm_check(release:"FC28", reference:"mosquitto-1.4.15-1.fc28")) 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_2018-E03A17FA61.NASL description Fix CVE-2017-7651 (rhbz#1551755, rhbz#1551754) 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 2018-04-03 plugin id 108792 published 2018-04-03 reporter This script is Copyright (C) 2018-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/108792 title Fedora 26 : mosquitto (2018-e03a17fa61) NASL family Fedora Local Security Checks NASL id FEDORA_2018-AD652798B8.NASL description Fix CVE-2017-7651 (rhbz#1551755, rhbz#1551754) 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 2018-04-03 plugin id 108791 published 2018-04-03 reporter This script is Copyright (C) 2018-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/108791 title Fedora 27 : mosquitto (2018-ad652798b8) NASL family Debian Local Security Checks NASL id DEBIAN_DSA-4325.NASL description It was discovered that mosquitto, an MQTT broker, was vulnerable to remote denial-of-service attacks that could be mounted using various vectors. last seen 2020-06-01 modified 2020-06-02 plugin id 118408 published 2018-10-26 reporter This script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/118408 title Debian DSA-4325-1 : mosquitto - security update NASL family Debian Local Security Checks NASL id DEBIAN_DLA-1334.NASL description CVE-2017-7651 A crafted CONNECT packet from an unauthenticated client could result in extraordinary memory consumption. CVE-2017-7652 In case all sockets/file descriptors are exhausted, a SIGHUP signal to reload the configuration could result in default config values (especially bad security settings) For Debian 7 last seen 2020-03-17 modified 2018-04-02 plugin id 108768 published 2018-04-02 reporter This script is Copyright (C) 2018-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/108768 title Debian DLA-1334-1 : mosquitto security update NASL family Debian Local Security Checks NASL id DEBIAN_DLA-1409.NASL description CVE-2017-7651 fix to avoid extraordinary memory consumption by crafted CONNECT packet from unauthenticated client CVE-2017-7652 in case all sockets/file descriptors are exhausted, this is a fix to avoid default config values after reloading configuration by SIGHUP signal For Debian 8 last seen 2020-06-01 modified 2020-06-02 plugin id 110818 published 2018-07-02 reporter This script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/110818 title Debian DLA-1409-1 : mosquitto security update
References
- https://bugs.eclipse.org/bugs/show_bug.cgi?id=529754
- https://lists.debian.org/debian-lts-announce/2018/03/msg00037.html
- https://lists.debian.org/debian-lts-announce/2018/06/msg00016.html
- https://mosquitto.org/blog/2018/02/security-advisory-cve-2017-7651-cve-2017-7652/
- https://www.debian.org/security/2018/dsa-4325