Vulnerabilities > CVE-2019-5885 - Use of Insufficiently Random Values vulnerability in multiple products
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
NONE Integrity impact
HIGH Availability impact
NONE Summary
Matrix Synapse before 0.34.0.1, when the macaroon_secret_key authentication parameter is not set, uses a predictable value to derive a secret key and other secrets which could allow remote attackers to impersonate users.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Brute Force In this attack, some asset (information, functionality, identity, etc.) is protected by a finite secret value. The attacker attempts to gain access to this asset by using trial-and-error to exhaustively explore all the possible secret values in the hope of finding the secret (or a value that is functionally equivalent) that will unlock the asset. Examples of secrets can include, but are not limited to, passwords, encryption keys, database lookup keys, and initial values to one-way functions. The key factor in this attack is the attackers' ability to explore the possible secret space rapidly. This, in turn, is a function of the size of the secret space and the computational power the attacker is able to bring to bear on the problem. If the attacker has modest resources and the secret space is large, the challenge facing the attacker is intractable. While the defender cannot control the resources available to an attacker, they can control the size of the secret space. Creating a large secret space involves selecting one's secret from as large a field of equally likely alternative secrets as possible and ensuring that an attacker is unable to reduce the size of this field using available clues or cryptanalysis. Doing this is more difficult than it sounds since elimination of patterns (which, in turn, would provide an attacker clues that would help them reduce the space of potential secrets) is difficult to do using deterministic machines, such as computers. Assuming a finite secret space, a brute force attack will eventually succeed. The defender must rely on making sure that the time and resources necessary to do so will exceed the value of the information. For example, a secret space that will likely take hundreds of years to explore is likely safe from raw-brute force attacks.
- Signature Spoofing by Key Recreation An attacker obtains an authoritative or reputable signer's private signature key by exploiting a cryptographic weakness in the signature algorithm or pseudorandom number generation and then uses this key to forge signatures from the original signer to mislead a victim into performing actions that benefit the attacker.
- Session Credential Falsification through Prediction This attack targets predictable session ID in order to gain privileges. The attacker can predict the session ID used during a transaction to perform spoofing and session hijacking.
Nessus
NASL family Fedora Local Security Checks NASL id FEDORA_2019-C6044B3FCE.NASL description Fix for CVE-2019-5885 Upgrade notes available at https://github.com/matrix-org/synapse/blob/v0.34.0/UPGRADE.rst#upgradi ng-to-v0340 - Note this continues to use Python 2. 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 2020-03-18 modified 2019-01-23 plugin id 121323 published 2019-01-23 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/121323 title Fedora 28 : matrix-synapse (2019-c6044b3fce) code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from Fedora Security Advisory FEDORA-2019-c6044b3fce. # include("compat.inc"); if (description) { script_id(121323); script_version("1.4"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/02/24"); script_cve_id("CVE-2019-5885"); script_xref(name:"FEDORA", value:"2019-c6044b3fce"); script_name(english:"Fedora 28 : matrix-synapse (2019-c6044b3fce)"); 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 for CVE-2019-5885 Upgrade notes available at https://github.com/matrix-org/synapse/blob/v0.34.0/UPGRADE.rst#upgradi ng-to-v0340 - Note this continues to use Python 2. 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-2019-c6044b3fce" ); # https://github.com/matrix-org/synapse/blob/v0.34.0/UPGRADE.rst#upgrading-to-v0340 script_set_attribute( attribute:"see_also", value:"http://www.nessus.org/u?7676fa79" ); script_set_attribute( attribute:"solution", value:"Update the affected matrix-synapse package." ); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/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:N/UI:N/S:U/C:N/I:H/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:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:matrix-synapse"); script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:28"); script_set_attribute(attribute:"vuln_publication_date", value:"2019/03/21"); script_set_attribute(attribute:"patch_publication_date", value:"2019/01/23"); script_set_attribute(attribute:"plugin_publication_date", value:"2019/01/23"); 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:"matrix-synapse-0.34.0.1-2.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, "matrix-synapse"); }
NASL family FreeBSD Local Security Checks NASL id FREEBSD_PKG_383931BA181811E992EA448A5B29E8A9.NASL description Matrix developers report : The matrix team announces the availablility of synapse security releases 0.34.0.1 and 0.34.1.1, fixing CVE-2019-5885. last seen 2020-03-18 modified 2019-01-16 plugin id 121199 published 2019-01-16 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/121199 title FreeBSD : py-matrix-synapse -- undisclosed vulnerability (383931ba-1818-11e9-92ea-448a5b29e8a9) 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(121199); script_version("1.3"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/02/24"); script_cve_id("CVE-2019-5885"); script_name(english:"FreeBSD : py-matrix-synapse -- undisclosed vulnerability (383931ba-1818-11e9-92ea-448a5b29e8a9)"); script_summary(english:"Checks for updated packages in pkg_info output"); script_set_attribute( attribute:"synopsis", value: "The remote FreeBSD host is missing one or more security-related updates." ); script_set_attribute( attribute:"description", value: "Matrix developers report : The matrix team announces the availablility of synapse security releases 0.34.0.1 and 0.34.1.1, fixing CVE-2019-5885." ); # https://matrix.org/blog/2019/01/10/critical-security-update-synapse-0-34-0-1-synapse-0-34-1-1/ script_set_attribute( attribute:"see_also", value:"http://www.nessus.org/u?6c1bc623" ); # https://vuxml.freebsd.org/freebsd/383931ba-1818-11e9-92ea-448a5b29e8a9.html script_set_attribute( attribute:"see_also", value:"http://www.nessus.org/u?21d40b59" ); script_set_attribute(attribute:"solution", value:"Update the affected packages."); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/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:N/UI:N/S:U/C:N/I:H/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:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:py27-matrix-synapse"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:py35-matrix-synapse"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:py36-matrix-synapse"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:py37-matrix-synapse"); script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd"); script_set_attribute(attribute:"vuln_publication_date", value:"2019/01/10"); script_set_attribute(attribute:"patch_publication_date", value:"2019/01/15"); script_set_attribute(attribute:"plugin_publication_date", value:"2019/01/16"); 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:"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:"py27-matrix-synapse<0.34.1.1")) flag++; if (pkg_test(save_report:TRUE, pkg:"py35-matrix-synapse<0.34.1.1")) flag++; if (pkg_test(save_report:TRUE, pkg:"py36-matrix-synapse<0.34.1.1")) flag++; if (pkg_test(save_report:TRUE, pkg:"py37-matrix-synapse<0.34.1.1")) 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_2019-4D914F9257.NASL description Fix for CVE-2019-5885 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 2020-03-17 modified 2019-01-23 plugin id 121319 published 2019-01-23 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/121319 title Fedora 29 : matrix-synapse (2019-4d914f9257)
References
- https://matrix.org/blog/2019/01/15/further-details-on-critical-security-update-in-synapse-affecting-all-versions-prior-to-0-34-1-cve-2019-5885/
- https://matrix.org/blog/2019/01/10/critical-security-update-synapse-0-34-0-1-synapse-0-34-1-1/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/32Y6KD3OAHCG5P33HC2QEX3NUZOSXCGZ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VMCLO5PUPBA756UKY72PKUWL4RRM4W6K/