Vulnerabilities > CVE-2020-10932 - Information Exposure Through Discrepancy vulnerability in multiple products
Summary
An issue was discovered in Arm Mbed TLS before 2.16.6 and 2.7.x before 2.7.15. An attacker that can get precise enough side-channel measurements can recover the long-term ECDSA private key by (1) reconstructing the projective coordinate of the result of scalar multiplication by exploiting side channels in the conversion to affine coordinates; (2) using an attack described by Naccache, Smart, and Stern in 2003 to recover a few bits of the ephemeral scalar from those projective coordinates via several measurements; and (3) using a lattice attack to get from there to the long-term ECDSA private key used for the signatures. Typically an attacker would have sufficient access when attacking an SGX enclave and controlling the untrusted OS.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Nessus
NASL family Fedora Local Security Checks NASL id FEDORA_2020-9A6E8E63E9.NASL description - Update to 2.16.6 Release notes: https://tls.mbed.org/tech-updates/releases/mbedtls-2.16.6-and-2.7.15-r eleased Security Advisory: https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security -advisory-2020-04 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 2020-06-10 modified 2020-06-05 plugin id 137162 published 2020-06-05 reporter This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/137162 title Fedora 32 : mbedtls (2020-9a6e8e63e9) code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from Fedora Security Advisory FEDORA-2020-9a6e8e63e9. # include("compat.inc"); if (description) { script_id(137162); script_version("1.2"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/09"); script_cve_id("CVE-2020-10932"); script_xref(name:"FEDORA", value:"2020-9a6e8e63e9"); script_name(english:"Fedora 32 : mbedtls (2020-9a6e8e63e9)"); 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 2.16.6 Release notes: https://tls.mbed.org/tech-updates/releases/mbedtls-2.16.6-and-2.7.15-r eleased Security Advisory: https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security -advisory-2020-04 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-2020-9a6e8e63e9" ); script_set_attribute( attribute:"solution", value:"Update the affected mbedtls package." ); script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/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:L/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:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:mbedtls"); script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:32"); script_set_attribute(attribute:"vuln_publication_date", value:"2020/04/15"); script_set_attribute(attribute:"patch_publication_date", value:"2020/06/05"); script_set_attribute(attribute:"plugin_publication_date", value:"2020/06/05"); 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:"^32([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 32", "Fedora " + os_ver); if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING); cpu = get_kb_item("Host/cpu"); if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH); if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu); flag = 0; if (rpm_check(release:"FC32", reference:"mbedtls-2.16.6-1.fc32")) flag++; if (flag) { security_report_v4( port : 0, severity : SECURITY_NOTE, 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, "mbedtls"); }
NASL family FreeBSD Local Security Checks NASL id FREEBSD_PKG_BF1F47C47F1B11EABF94001CC0382B2F.NASL description Manuel Pegourie-Gonnard reports : An attacker with access to precise enough timing and memory access information (typically an untrusted operating system attacking a secure enclave such as SGX or the TrustZone secure world) can fully recover an ECDSA private key after observing a number of signature operations. last seen 2020-04-30 modified 2020-04-16 plugin id 135604 published 2020-04-16 reporter This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/135604 title FreeBSD : Mbed TLS -- Side channel attack on ECDSA (bf1f47c4-7f1b-11ea-bf94-001cc0382b2f) 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(135604); script_version("1.3"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/04/27"); script_cve_id("CVE-2020-10932"); script_name(english:"FreeBSD : Mbed TLS -- Side channel attack on ECDSA (bf1f47c4-7f1b-11ea-bf94-001cc0382b2f)"); 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: "Manuel Pegourie-Gonnard reports : An attacker with access to precise enough timing and memory access information (typically an untrusted operating system attacking a secure enclave such as SGX or the TrustZone secure world) can fully recover an ECDSA private key after observing a number of signature operations." ); # https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-04 script_set_attribute( attribute:"see_also", value:"http://www.nessus.org/u?b66af52d" ); # https://vuxml.freebsd.org/freebsd/bf1f47c4-7f1b-11ea-bf94-001cc0382b2f.html script_set_attribute( attribute:"see_also", value:"http://www.nessus.org/u?9f2ee221" ); script_set_attribute(attribute:"solution", value:"Update the affected package."); script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/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:L/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:"cvss_score_source", value:"CVE-2020-10932"); 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:mbedtls"); script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd"); script_set_attribute(attribute:"vuln_publication_date", value:"2020/04/14"); script_set_attribute(attribute:"patch_publication_date", value:"2020/04/15"); script_set_attribute(attribute:"plugin_publication_date", value:"2020/04/16"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 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:"mbedtls<2.16.6")) flag++; if (flag) { if (report_verbosity > 0) security_note(port:0, extra:pkg_report_get()); else security_note(0); exit(0); } else audit(AUDIT_HOST_NOT, "affected");
NASL family Fedora Local Security Checks NASL id FEDORA_2020-42564738A1.NASL description - Update to 2.16.6 Release notes: https://tls.mbed.org/tech-updates/releases/mbedtls-2.16.6-and-2.7.15-r eleased Security Advisory: https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security -advisory-2020-04 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 2020-06-10 modified 2020-06-05 plugin id 137158 published 2020-06-05 reporter This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/137158 title Fedora 31 : mbedtls (2020-42564738a1) code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from Fedora Security Advisory FEDORA-2020-42564738a1. # include("compat.inc"); if (description) { script_id(137158); script_version("1.2"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/09"); script_cve_id("CVE-2020-10932"); script_xref(name:"FEDORA", value:"2020-42564738a1"); script_name(english:"Fedora 31 : mbedtls (2020-42564738a1)"); 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 2.16.6 Release notes: https://tls.mbed.org/tech-updates/releases/mbedtls-2.16.6-and-2.7.15-r eleased Security Advisory: https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security -advisory-2020-04 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-2020-42564738a1" ); # https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-04 script_set_attribute( attribute:"see_also", value:"http://www.nessus.org/u?b66af52d" ); script_set_attribute( attribute:"solution", value:"Update the affected mbedtls package." ); script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/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:L/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:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:mbedtls"); script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:31"); script_set_attribute(attribute:"vuln_publication_date", value:"2020/04/15"); script_set_attribute(attribute:"patch_publication_date", value:"2020/06/05"); script_set_attribute(attribute:"plugin_publication_date", value:"2020/06/05"); 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:"mbedtls-2.16.6-1.fc31")) flag++; if (flag) { security_report_v4( port : 0, severity : SECURITY_NOTE, 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, "mbedtls"); }
References
- https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-04
- https://tls.mbed.org/tech-updates/releases/mbedtls-2.16.6-and-2.7.15-released
- https://tls.mbed.org/tech-updates/security-advisories
- https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNOS2IIBH5WNJXZUV546PY7666DE7Y3L/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FCWN5HIF4CJ2LZTOMEBJ7Q4IMMV7ZU2V/