Vulnerabilities > CVE-2020-9369 - Resource Exhaustion vulnerability in multiple products
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
NONE Integrity impact
NONE Availability impact
HIGH Summary
Sympa 6.2.38 through 6.2.52 allows remote attackers to cause a denial of service (disk consumption from temporary files, and a flood of notifications to listmasters) via a series of requests with malformed parameters.
Vulnerable Configurations
Part | Description | Count |
---|---|---|
Application | 22 | |
OS | 3 | |
OS | 1 |
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_2020-79516CB689.NASL description Update to sympa 6.2.54 : - Fixes CVE-2020-9369 - See https://sympa-community.github.io/security/2020-001.html for details 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 2020-03-19 modified 2020-03-13 plugin id 134459 published 2020-03-13 reporter This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/134459 title Fedora 31 : sympa (2020-79516cb689) code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from Fedora Security Advisory FEDORA-2020-79516cb689. # include("compat.inc"); if (description) { script_id(134459); script_version("1.2"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/03/18"); script_cve_id("CVE-2020-9369"); script_xref(name:"FEDORA", value:"2020-79516cb689"); script_name(english:"Fedora 31 : sympa (2020-79516cb689)"); 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: "Update to sympa 6.2.54 : - Fixes CVE-2020-9369 - See https://sympa-community.github.io/security/2020-001.html for details 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-2020-79516cb689" ); script_set_attribute( attribute:"see_also", value:"https://sympa-community.github.io/security/2020-001.html" ); script_set_attribute(attribute:"solution", value:"Update the affected sympa package."); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/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:L/PR:N/UI:N/S:U/C:N/I:N/A:H"); 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:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:sympa"); script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:31"); script_set_attribute(attribute:"vuln_publication_date", value:"2020/02/24"); script_set_attribute(attribute:"patch_publication_date", value:"2020/03/12"); script_set_attribute(attribute:"plugin_publication_date", value:"2020/03/13"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 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:"^31([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 31", "Fedora " + os_ver); if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING); cpu = get_kb_item("Host/cpu"); if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH); if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu); flag = 0; if (rpm_check(release:"FC31", reference:"sympa-6.2.54-1.fc31")) 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, "sympa"); }
NASL family FreeBSD Local Security Checks NASL id FREEBSD_PKG_9908A1CC35AD424DBE0B7E56ABD5931A.NASL description Javier Moreno discovered a vulnerability in Sympa web interface that can cause denial of service (DoS) attack. By submitting requests with malformed parameters, this flaw allows to create junk files in Sympa last seen 2020-06-06 modified 2020-05-28 plugin id 136941 published 2020-05-28 reporter This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/136941 title FreeBSD : sympa -- Denial of service caused by malformed CSRF token (9908a1cc-35ad-424d-be0b-7e56abd5931a) code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from the FreeBSD VuXML database : # # Copyright 2003-2020 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(136941); script_version("1.2"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/05"); script_cve_id("CVE-2020-9369"); script_name(english:"FreeBSD : sympa -- Denial of service caused by malformed CSRF token (9908a1cc-35ad-424d-be0b-7e56abd5931a)"); 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: "Javier Moreno discovered a vulnerability in Sympa web interface that can cause denial of service (DoS) attack. By submitting requests with malformed parameters, this flaw allows to create junk files in Sympa's directory for temporary files. And particularly by tampering token to prevent CSRF, it allows to originate exessive notification messages to listmasters." ); script_set_attribute( attribute:"see_also", value:"https://sympa-community.github.io/security/2020-001.html" ); # https://vuxml.freebsd.org/freebsd/9908a1cc-35ad-424d-be0b-7e56abd5931a.html script_set_attribute( attribute:"see_also", value:"http://www.nessus.org/u?53884a0c" ); 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:N/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:L/PR:N/UI:N/S:U/C:N/I:N/A:H"); 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:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:sympa"); script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd"); script_set_attribute(attribute:"vuln_publication_date", value:"2020/02/24"); script_set_attribute(attribute:"patch_publication_date", value:"2020/05/22"); script_set_attribute(attribute:"plugin_publication_date", value:"2020/05/28"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2020 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:"sympa<6.2.54")) 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 Fedora Local Security Checks NASL id FEDORA_2020-BB5AA250C9.NASL description Update to sympa 6.2.54 : - Fixes CVE-2020-9369 - See https://sympa-community.github.io/security/2020-001.html for details 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 2020-03-19 modified 2020-03-13 plugin id 134463 published 2020-03-13 reporter This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/134463 title Fedora 30 : sympa (2020-bb5aa250c9) code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from Fedora Security Advisory FEDORA-2020-bb5aa250c9. # include("compat.inc"); if (description) { script_id(134463); script_version("1.2"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/03/18"); script_cve_id("CVE-2020-9369"); script_xref(name:"FEDORA", value:"2020-bb5aa250c9"); script_name(english:"Fedora 30 : sympa (2020-bb5aa250c9)"); 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: "Update to sympa 6.2.54 : - Fixes CVE-2020-9369 - See https://sympa-community.github.io/security/2020-001.html for details 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-2020-bb5aa250c9" ); script_set_attribute( attribute:"see_also", value:"https://sympa-community.github.io/security/2020-001.html" ); script_set_attribute(attribute:"solution", value:"Update the affected sympa package."); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/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:L/PR:N/UI:N/S:U/C:N/I:N/A:H"); 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:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:sympa"); script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:30"); script_set_attribute(attribute:"vuln_publication_date", value:"2020/02/24"); script_set_attribute(attribute:"patch_publication_date", value:"2020/03/13"); script_set_attribute(attribute:"plugin_publication_date", value:"2020/03/13"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 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:"^30([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 30", "Fedora " + os_ver); if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING); cpu = get_kb_item("Host/cpu"); if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH); if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu); flag = 0; if (rpm_check(release:"FC30", reference:"sympa-6.2.54-1.fc30")) 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, "sympa"); }
References
- https://github.com/sympa-community/sympa/issues/886
- https://sympa-community.github.io/security/2020-001.html
- https://www.debian.org/security/2020/dsa-4818
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XO4WJYNNHWM7DUKCN4EWYYYPXZSOI7BQ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6TMVZ5LVYCCIHGEC7RQUMGUE7DJWUXN7/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A3FUYYLV6URRLAJVWXNJYK2CNOKKNHXC/