Vulnerabilities > CVE-2018-12435 - Information Exposure vulnerability in Botan Project Botan 2.5.0/2.6.0/2.7.0

047910
CVSS 5.9 - MEDIUM
Attack vector
LOCAL
Attack complexity
HIGH
Privileges required
NONE
Confidentiality impact
HIGH
Integrity impact
NONE
Availability impact
NONE
local
high complexity
botan-project
CWE-200
nessus
NVD
Published: 2018-06-15
Updated: 2024-11-21

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
Botan_Project
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 familyFedora Local Security Checks
    NASL idFEDORA_2018-98AB6B4E56.NASL
    descriptionUpdate 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 seen2020-06-05
    modified2018-07-12
    plugin id111016
    published2018-07-12
    reporterThis script is Copyright (C) 2018-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/111016
    titleFedora 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 familyFedora Local Security Checks
    NASL idFEDORA_2018-EAA7DE17AE.NASL
    descriptionUpdate 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 seen2020-06-05
    modified2019-01-03
    plugin id120879
    published2019-01-03
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/120879
    titleFedora 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 familyFreeBSD Local Security Checks
    NASL idFREEBSD_PKG_7762D7AD2E3841D29785C51F653BA8BD.NASL
    descriptionbotan2 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 seen2020-06-01
    modified2020-06-02
    plugin id111991
    published2018-08-20
    reporterThis script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/111991
    titleFreeBSD : botan2 -- ECDSA side channel (7762d7ad-2e38-41d2-9785-c51f653ba8bd)

References