Vulnerabilities > CVE-2018-12435 - Information Exposure vulnerability in Botan Project Botan 2.5.0/2.6.0/2.7.0
Attack vector
LOCAL Attack complexity
MEDIUM Privileges required
NONE Confidentiality impact
PARTIAL Integrity impact
NONE Availability impact
NONE Summary
Botan 2.5.0 through 2.6.0 before 2.7.0 allows a memory-cache side-channel attack on ECDSA signatures, aka the Return Of the Hidden Number Problem or ROHNP, related to dsa/dsa.cpp, ec_group/ec_group.cpp, and ecdsa/ecdsa.cpp. To discover an ECDSA key, the attacker needs access to either the local machine or a different virtual machine on the same physical host.
Vulnerable Configurations
| Part | Description | Count |
|---|---|---|
| Application | 3 |
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Subverting Environment Variable Values The attacker directly or indirectly modifies environment variables used by or controlling the target software. The attacker's goal is to cause the target software to deviate from its expected operation in a manner that benefits the attacker.
- Footprinting An attacker engages in probing and exploration activity to identify constituents and properties of the target. Footprinting is a general term to describe a variety of information gathering techniques, often used by attackers in preparation for some attack. It consists of using tools to learn as much as possible about the composition, configuration, and security mechanisms of the targeted application, system or network. Information that might be collected during a footprinting effort could include open ports, applications and their versions, network topology, and similar information. While footprinting is not intended to be damaging (although certain activities, such as network scans, can sometimes cause disruptions to vulnerable applications inadvertently) it may often pave the way for more damaging attacks.
- 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.
- Browser Fingerprinting An attacker carefully crafts small snippets of Java Script to efficiently detect the type of browser the potential victim is using. Many web-based attacks need prior knowledge of the web browser including the version of browser to ensure successful exploitation of a vulnerability. Having this knowledge allows an attacker to target the victim with attacks that specifically exploit known or zero day weaknesses in the type and version of the browser used by the victim. Automating this process via Java Script as a part of the same delivery system used to exploit the browser is considered more efficient as the attacker can supply a browser fingerprinting method and integrate it with exploit code, all contained in Java Script and in response to the same web page request by the browser.
- 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_2018-98AB6B4E56.NASL description Update Botan2 to 2.7.0. Focus of this release is on performance and side channel hardening. - Address side channels in RSA key generation and ECDSA signing - Side channel hardening in many core algorithms (modular exponentiation, ECC scalar multiply, Karatsuba multiplication, Barrett reduction, etc) to reduce the risk of future exploitable side channels. - Many optimizations for ECC operations, RSA (including key gen), DSA, DH, and XMSS. Typical speedups vs 2.6.0 is 10 to 40% depending on operation and key size. - Add Scrypt password hashing. Also supported is using Scrypt to derive keys for private key encryption (format compatible with upcoming OpenSSL 1.1.1) - Add base32 encoding/decoding - Plus many bug fixes and smaller enhancements documented in the [release notes](https://botan.randombit.net/news.html#version-2-7 -0-2018-07-02) 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 2018-07-12 plugin id 111016 published 2018-07-12 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/111016 title Fedora 27 : botan2 (2018-98ab6b4e56) 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-2018-98ab6b4e56. # include("compat.inc"); if (description) { script_id(111016); script_version("1.5"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04"); script_cve_id("CVE-2018-0495", "CVE-2018-12435"); script_xref(name:"FEDORA", value:"2018-98ab6b4e56"); script_name(english:"Fedora 27 : botan2 (2018-98ab6b4e56)"); 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 Botan2 to 2.7.0. Focus of this release is on performance and side channel hardening. - Address side channels in RSA key generation and ECDSA signing - Side channel hardening in many core algorithms (modular exponentiation, ECC scalar multiply, Karatsuba multiplication, Barrett reduction, etc) to reduce the risk of future exploitable side channels. - Many optimizations for ECC operations, RSA (including key gen), DSA, DH, and XMSS. Typical speedups vs 2.6.0 is 10 to 40% depending on operation and key size. - Add Scrypt password hashing. Also supported is using Scrypt to derive keys for private key encryption (format compatible with upcoming OpenSSL 1.1.1) - Add base32 encoding/decoding - Plus many bug fixes and smaller enhancements documented in the [release notes](https://botan.randombit.net/news.html#version-2-7 -0-2018-07-02) 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-2018-98ab6b4e56" ); script_set_attribute( attribute:"see_also", value:"https://botan.randombit.net/news.html#version-2-7-0-2018-07-02" ); script_set_attribute( attribute:"solution", value:"Update the affected botan2 package." ); script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/C:P/I:N/A:N"); script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:N/UI:N/S:C/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:botan2"); script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:27"); script_set_attribute(attribute:"vuln_publication_date", value:"2018/06/13"); script_set_attribute(attribute:"patch_publication_date", value:"2018/07/11"); script_set_attribute(attribute:"plugin_publication_date", value:"2018/07/12"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2018-2020 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:"^27([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 27", "Fedora " + os_ver); if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING); cpu = get_kb_item("Host/cpu"); if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH); if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu); flag = 0; if (rpm_check(release:"FC27", reference:"botan2-2.7.0-1.fc27")) 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, "botan2"); }NASL family Fedora Local Security Checks NASL id FEDORA_2018-EAA7DE17AE.NASL description Update Botan2 to 2.7.0. Focus of this release is on performance and side channel hardening. - Address side channels in RSA key generation and ECDSA signing - Side channel hardening in many core algorithms (modular exponentiation, ECC scalar multiply, Karatsuba multiplication, Barrett reduction, etc) to reduce the risk of future exploitable side channels. - Many optimizations for ECC operations, RSA (including key gen), DSA, DH, and XMSS. Typical speedups vs 2.6.0 is 10 to 40% depending on operation and key size. - Add Scrypt password hashing. Also supported is using Scrypt to derive keys for private key encryption (format compatible with upcoming OpenSSL 1.1.1) - Add base32 encoding/decoding - Plus many bug fixes and smaller enhancements documented in the [release notes](https://botan.randombit.net/news.html#version-2-7 -0-2018-07-02) 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 120879 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/120879 title Fedora 28 : botan2 (2018-eaa7de17ae) 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-eaa7de17ae. # include("compat.inc"); if (description) { script_id(120879); script_version("1.4"); script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04"); script_cve_id("CVE-2018-0495", "CVE-2018-12435"); script_xref(name:"FEDORA", value:"2018-eaa7de17ae"); script_name(english:"Fedora 28 : botan2 (2018-eaa7de17ae)"); 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 Botan2 to 2.7.0. Focus of this release is on performance and side channel hardening. - Address side channels in RSA key generation and ECDSA signing - Side channel hardening in many core algorithms (modular exponentiation, ECC scalar multiply, Karatsuba multiplication, Barrett reduction, etc) to reduce the risk of future exploitable side channels. - Many optimizations for ECC operations, RSA (including key gen), DSA, DH, and XMSS. Typical speedups vs 2.6.0 is 10 to 40% depending on operation and key size. - Add Scrypt password hashing. Also supported is using Scrypt to derive keys for private key encryption (format compatible with upcoming OpenSSL 1.1.1) - Add base32 encoding/decoding - Plus many bug fixes and smaller enhancements documented in the [release notes](https://botan.randombit.net/news.html#version-2-7 -0-2018-07-02) 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-eaa7de17ae" ); script_set_attribute( attribute:"see_also", value:"https://botan.randombit.net/news.html#version-2-7-0-2018-07-02" ); script_set_attribute( attribute:"solution", value:"Update the affected botan2 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:H/PR:N/UI:N/S:C/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:botan2"); script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:28"); script_set_attribute(attribute:"vuln_publication_date", value:"2018/06/13"); script_set_attribute(attribute:"patch_publication_date", value:"2018/07/11"); 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:"botan2-2.7.0-1.fc28")) 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, "botan2"); }NASL family FreeBSD Local Security Checks NASL id FREEBSD_PKG_7762D7AD2E3841D29785C51F653BA8BD.NASL description botan2 developers report : A side channel in the ECDSA signature operation could allow a local attacker to recover the secret key. Found by Keegan Ryan of NCC Group. Bug introduced in 2.5.0, fixed in 2.7.0. The 1.10 branch is not affected. last seen 2020-06-01 modified 2020-06-02 plugin id 111991 published 2018-08-20 reporter This script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/111991 title FreeBSD : botan2 -- ECDSA side channel (7762d7ad-2e38-41d2-9785-c51f653ba8bd)