Vulnerabilities > CVE-2020-13777 - Use of a Broken or Risky Cryptographic Algorithm vulnerability in multiple products

047910
CVSS 7.4 - HIGH
Attack vector
NETWORK
Attack complexity
HIGH
Privileges required
NONE
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
NONE
network
high complexity
gnu
fedoraproject
canonical
debian
CWE-327
nessus
NVD
Published: 2020-06-04
Updated: 2024-11-21

Summary

GnuTLS 3.6.x before 3.6.14 uses incorrect cryptography for encrypting a session ticket (a loss of confidentiality in TLS 1.2, and an authentication bypass in TLS 1.3). The earliest affected version is 3.6.4 (2018-09-24) because of an error in a 2018-09-18 commit. Until the first key rotation, the TLS server always uses wrong data in place of an encryption key derived from an application.

Vulnerable Configurations

Part Description Count
Application
Gnu
15
OS
Fedoraproject
2
OS
Canonical
2
OS
Debian
1

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Encryption Brute Forcing
    An attacker, armed with the cipher text and the encryption algorithm used, performs an exhaustive (brute force) search on the key space to determine the key that decrypts the cipher text to obtain the plaintext.
  • Creating a Rogue Certificate Authority Certificate
    An attacker exploits a weakness in the MD5 hash algorithm (weak collision resistance) to generate a certificate signing request (CSR) that contains collision blocks in the "to be signed" part. The attacker specially crafts two different, but valid X.509 certificates that when hashed with the MD5 algorithm would yield the same value. The attacker then sends the CSR for one of the certificates to the Certification Authority which uses the MD5 hashing algorithm. That request is completely valid and the Certificate Authority issues an X.509 certificate to the attacker which is signed with its private key. An attacker then takes that signed blob and inserts it into another X.509 certificate that the attacker generated. Due to the MD5 collision, both certificates, though different, hash to the same value and so the signed blob works just as well in the second certificate. The net effect is that the attackers' second X.509 certificate, which the Certification Authority has never seen, is now signed and validated by that Certification Authority. To make the attack more interesting, the second certificate could be not just a regular certificate, but rather itself a signing certificate. Thus the attacker is able to start their own Certification Authority that is anchored in its root of trust in the legitimate Certification Authority that has signed the attackers' first X.509 certificate. If the original Certificate Authority was accepted by default by browsers, so will now the Certificate Authority set up by the attacker and of course any certificates that it signs. So the attacker is now able to generate any SSL certificates to impersonate any web server, and the user's browser will not issue any warning to the victim. This can be used to compromise HTTPS communications and other types of systems where PKI and X.509 certificates may be used (e.g., VPN, IPSec) .
  • Signature Spoof
    An attacker generates a message or datablock that causes the recipient to believe that the message or datablock was generated and cryptographically signed by an authoritative or reputable source, misleading a victim or victim operating system into performing malicious actions.
  • Cryptanalysis
    Cryptanalysis is a process of finding weaknesses in cryptographic algorithms and using these weaknesses to decipher the ciphertext without knowing the secret key (instance deduction). Sometimes the weakness is not in the cryptographic algorithm itself, but rather in how it is applied that makes cryptanalysis successful. An attacker may have other goals as well, such as: 1. Total Break - Finding the secret key 2. Global Deduction - Finding a functionally equivalent algorithm for encryption and decryption that does not require knowledge of the secret key. 3. Information Deduction - Gaining some information about plaintexts or ciphertexts that was not previously known 4. Distinguishing Algorithm - The attacker has the ability to distinguish the output of the encryption (ciphertext) from a random permutation of bits The goal of the attacker performing cryptanalysis will depend on the specific needs of the attacker in a given attack context. In most cases, if cryptanalysis is successful at all, an attacker will not be able to go past being able to deduce some information about the plaintext (goal 3). However, that may be sufficient for an attacker, depending on the context.

Nessus

  • NASL familySuSE Local Security Checks
    NASL idOPENSUSE-2020-790.NASL
    descriptionThis update for gnutls fixes the following issues : - CVE-2020-13777: Fixed an insecure session ticket key construction which could have made the TLS server to not bind the session ticket encryption key with a value supplied by the application until the initial key rotation, allowing an attacker to bypass authentication in TLS 1.3 and recover previous conversations in TLS 1.2 (bsc#1172506). - Fixed an improper handling of certificate chain with cross-signed intermediate CA certificates (bsc#1172461). This update was imported from the SUSE:SLE-15:Update update project.
    last seen2020-06-12
    modified2020-06-11
    plugin id137350
    published2020-06-11
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/137350
    titleopenSUSE Security Update : gnutls (openSUSE-2020-790)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from openSUSE Security Update openSUSE-2020-790.
#
# The text description of this plugin is (C) SUSE LLC.
#

include("compat.inc");

if (description)
{
  script_id(137350);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/18");

  script_cve_id("CVE-2020-13777");

  script_name(english:"openSUSE Security Update : gnutls (openSUSE-2020-790)");
  script_summary(english:"Check for the openSUSE-2020-790 patch");

  script_set_attribute(
    attribute:"synopsis",
    value:"The remote openSUSE host is missing a security update."
  );
  script_set_attribute(
    attribute:"description",
    value:
"This update for gnutls fixes the following issues :

  - CVE-2020-13777: Fixed an insecure session ticket key
    construction which could have made the TLS server to not
    bind the session ticket encryption key with a value
    supplied by the application until the initial key
    rotation, allowing an attacker to bypass authentication
    in TLS 1.3 and recover previous conversations in TLS 1.2
    (bsc#1172506).

  - Fixed an improper handling of certificate chain with
    cross-signed intermediate CA certificates (bsc#1172461).

This update was imported from the SUSE:SLE-15:Update update project."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.opensuse.org/show_bug.cgi?id=1172461"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.opensuse.org/show_bug.cgi?id=1172506"
  );
  script_set_attribute(
    attribute:"solution",
    value:"Update the affected gnutls packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/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:H/PR:N/UI:N/S:U/C:H/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:novell:opensuse:gnutls");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:gnutls-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:gnutls-debugsource");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:gnutls-guile");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:gnutls-guile-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutls-dane-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutls-dane0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutls-dane0-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutls-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutls-devel-32bit");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutls30");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutls30-32bit");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutls30-32bit-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutls30-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutls30-hmac");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutls30-hmac-32bit");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutlsxx-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutlsxx28");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libgnutlsxx28-debuginfo");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:opensuse:15.1");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/06/04");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/06/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/06/11");
  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:"SuSE Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/SuSE/release", "Host/SuSE/rpm-list", "Host/cpu");

  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/SuSE/release");
if (isnull(release) || release =~ "^(SLED|SLES)") audit(AUDIT_OS_NOT, "openSUSE");
if (release !~ "^(SUSE15\.1)$") audit(AUDIT_OS_RELEASE_NOT, "openSUSE", "15.1", release);
if (!get_kb_item("Host/SuSE/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

ourarch = get_kb_item("Host/cpu");
if (!ourarch) audit(AUDIT_UNKNOWN_ARCH);
if (ourarch !~ "^(i586|i686|x86_64)$") audit(AUDIT_ARCH_NOT, "i586 / i686 / x86_64", ourarch);

flag = 0;

if ( rpm_check(release:"SUSE15.1", reference:"gnutls-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"gnutls-debuginfo-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"gnutls-debugsource-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"gnutls-guile-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"gnutls-guile-debuginfo-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"libgnutls-dane-devel-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"libgnutls-dane0-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"libgnutls-dane0-debuginfo-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"libgnutls-devel-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"libgnutls30-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"libgnutls30-debuginfo-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"libgnutls30-hmac-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"libgnutlsxx-devel-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"libgnutlsxx28-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"libgnutlsxx28-debuginfo-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", cpu:"x86_64", reference:"libgnutls-devel-32bit-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", cpu:"x86_64", reference:"libgnutls30-32bit-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", cpu:"x86_64", reference:"libgnutls30-32bit-debuginfo-3.6.7-lp151.2.18.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", cpu:"x86_64", reference:"libgnutls30-hmac-32bit-3.6.7-lp151.2.18.1") ) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "gnutls / gnutls-debuginfo / gnutls-debugsource / gnutls-guile / etc");
}
  • NASL familyGentoo Local Security Checks
    NASL idGENTOO_GLSA-202006-01.NASL
    descriptionThe remote host is affected by the vulnerability described in GLSA-202006-01 (GnuTLS: Information disclosure) A flaw was reported in the TLS session ticket key construction in GnuTLS. Impact : A remote attacker could recover previous conversations in TLS 1.2 and obtain sensitive information or conduct a man-in-the-middle attack to bypass authentication in TLS 1.3. Workaround : There is no known workaround at this time.
    last seen2020-06-13
    modified2020-06-10
    plugin id137288
    published2020-06-10
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/137288
    titleGLSA-202006-01 : GnuTLS: Information disclosure
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Gentoo Linux Security Advisory GLSA 202006-01.
#
# The advisory text is Copyright (C) 2001-2020 Gentoo Foundation, Inc.
# and licensed under the Creative Commons - Attribution / Share Alike 
# license. See http://creativecommons.org/licenses/by-sa/3.0/
#

include("compat.inc");

if (description)
{
  script_id(137288);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/12");

  script_cve_id("CVE-2020-13777");
  script_xref(name:"GLSA", value:"202006-01");

  script_name(english:"GLSA-202006-01 : GnuTLS: Information disclosure");
  script_summary(english:"Checks for updated package(s) in /var/db/pkg");

  script_set_attribute(
    attribute:"synopsis",
    value:
"The remote Gentoo host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description",
    value:
"The remote host is affected by the vulnerability described in GLSA-202006-01
(GnuTLS: Information disclosure)

    A flaw was reported in the TLS session ticket key construction in
      GnuTLS.
  
Impact :

    A remote attacker could recover previous conversations in TLS 1.2 and
      obtain sensitive information or conduct a man-in-the-middle attack to
      bypass authentication in TLS 1.3.
  
Workaround :

    There is no known workaround at this time."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://security.gentoo.org/glsa/202006-01"
  );
  script_set_attribute(
    attribute:"solution",
    value:
"All GnuTLS user should upgrade to the latest version:
      # emerge --sync
      # emerge --ask --oneshot --verbose '>=net-libs/gnutls-3.6.14'"
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/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:H/PR:N/UI:N/S:U/C:H/I:H/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-2020-13777");
  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:gentoo:linux:gnutls");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/06/04");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/06/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/06/10");
  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:"Gentoo Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Gentoo/release", "Host/Gentoo/qpkg-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("qpkg.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Gentoo/release")) audit(AUDIT_OS_NOT, "Gentoo");
if (!get_kb_item("Host/Gentoo/qpkg-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;

if (qpkg_check(package:"net-libs/gnutls", unaffected:make_list("ge 3.6.14"), vulnerable:make_list("lt 3.6.14"))) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:qpkg_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = qpkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "GnuTLS");
}
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2020-0CCE3578E2.NASL
    descriptionUpdate to upstream 3.6.14 release, and security fix for CVE-2020-13777. 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 seen2020-06-13
    modified2020-06-08
    plugin id137211
    published2020-06-08
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/137211
    titleFedora 32 : gnutls (2020-0cce3578e2)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Fedora Security Advisory FEDORA-2020-0cce3578e2.
#

include("compat.inc");

if (description)
{
  script_id(137211);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/12");

  script_cve_id("CVE-2020-13777");
  script_xref(name:"FEDORA", value:"2020-0cce3578e2");

  script_name(english:"Fedora 32 : gnutls (2020-0cce3578e2)");
  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 upstream 3.6.14 release, and security fix for
CVE-2020-13777.

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-2020-0cce3578e2"
  );
  script_set_attribute(
    attribute:"solution",
    value:"Update the affected gnutls package."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/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:H/PR:N/UI:N/S:U/C:H/I:H/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-2020-13777");
  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:gnutls");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:32");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/06/04");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/06/07");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/06/08");
  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:"gnutls-3.6.14-1.fc32")) 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, "gnutls");
}
  • NASL familyUbuntu Local Security Checks
    NASL idUBUNTU_USN-4384-1.NASL
    descriptionIt was discovered that GnuTLS incorrectly handled session ticket encryption keys. A remote attacker could possibly use this issue to bypass authentication or recover sensitive information. Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-13
    modified2020-06-08
    plugin id137232
    published2020-06-08
    reporterUbuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/137232
    titleUbuntu 19.10 / 20.04 : gnutls28 vulnerability (USN-4384-1)
  • NASL familyFreeBSD Local Security Checks
    NASL idFREEBSD_PKG_EF5B4F5FA65811EA80D7001CC0382B2F.NASL
    descriptionThe GnuTLS project reports : It was found that GnuTLS 3.6.4 introduced a regression in the TLS protocol implementation. This caused the TLS server to not securely construct a session ticket encryption key considering the application supplied secret, allowing a MitM attacker to bypass authentication in TLS 1.3 and recover previous conversations in TLS 1.2.
    last seen2020-06-13
    modified2020-06-05
    plugin id137169
    published2020-06-05
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/137169
    titleFreeBSD : GnuTLS -- flaw in TLS session ticket key construction (ef5b4f5f-a658-11ea-80d7-001cc0382b2f)
  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DSA-4697.NASL
    descriptionA flaw was reported in the TLS session ticket key construction in GnuTLS, a library implementing the TLS and SSL protocols. The flaw caused the TLS server to not securely construct a session ticket encryption key considering the application supplied secret, allowing a man-in-the-middle attacker to bypass authentication in TLS 1.3 and recover previous conversations in TLS 1.2.
    last seen2020-06-13
    modified2020-06-08
    plugin id137209
    published2020-06-08
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/137209
    titleDebian DSA-4697-1 : gnutls28 - security update

References