An out of bounds read flaw was discovered in libssh2 in the way SSH_MSG_CHANNEL_REQUEST packets with an exit status message and no payload are parsed. A remote attacker who compromises a SSH server may be able to cause a denial of service or read data in the client memory. (CVE-2019-3862)
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALAS-2019-1303.
#
include('compat.inc');
if (description)
{
script_id(129561);
script_version("1.3");
script_set_attribute(attribute:"plugin_modification_date", value:"2024/04/19");
script_cve_id("CVE-2019-3862");
script_xref(name:"ALAS", value:"2019-1303");
script_name(english:"Amazon Linux 2 : libssh2 (ALAS-2019-1303)");
script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux 2 host is missing a security update.");
script_set_attribute(attribute:"description", value:
"An out of bounds read flaw was discovered in libssh2 in the way
SSH_MSG_CHANNEL_REQUEST packets with an exit status message and no
payload are parsed. A remote attacker who compromises a SSH server may
be able to cause a denial of service or read data in the client
memory. (CVE-2019-3862)");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/AL2/ALAS-2019-1303.html");
script_set_attribute(attribute:"solution", value:
"Run 'yum update libssh2' to update your system.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:P");
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:H/I:N/A:H");
script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2019-3862");
script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
script_set_attribute(attribute:"exploit_available", value:"false");
script_set_attribute(attribute:"vuln_publication_date", value:"2019/03/21");
script_set_attribute(attribute:"patch_publication_date", value:"2019/10/02");
script_set_attribute(attribute:"plugin_publication_date", value:"2019/10/04");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libssh2");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libssh2-debuginfo");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libssh2-devel");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libssh2-docs");
script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Amazon Linux Local Security Checks");
script_copyright(english:"This script is Copyright (C) 2019-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ssh_get_info.nasl");
script_require_keys("Host/local_checks_enabled", "Host/AmazonLinux/release", "Host/AmazonLinux/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/AmazonLinux/release");
if (isnull(release) || !strlen(release)) audit(AUDIT_OS_NOT, "Amazon Linux");
os_ver = pregmatch(pattern: "^AL(A|\d)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Amazon Linux");
os_ver = os_ver[1];
if (os_ver != "2")
{
if (os_ver == 'A') os_ver = 'AMI';
audit(AUDIT_OS_NOT, "Amazon Linux 2", "Amazon Linux " + os_ver);
}
if (!get_kb_item("Host/AmazonLinux/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);
flag = 0;
if (rpm_check(release:"AL2", reference:"libssh2-1.4.3-12.amzn2.2.2")) flag++;
if (rpm_check(release:"AL2", reference:"libssh2-debuginfo-1.4.3-12.amzn2.2.2")) flag++;
if (rpm_check(release:"AL2", reference:"libssh2-devel-1.4.3-12.amzn2.2.2")) flag++;
if (rpm_check(release:"AL2", reference:"libssh2-docs-1.4.3-12.amzn2.2.2")) 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, "libssh2 / libssh2-debuginfo / libssh2-devel / libssh2-docs");
}
Vendor | Product | Version | CPE |
---|---|---|---|
amazon | linux | libssh2 | p-cpe:/a:amazon:linux:libssh2 |
amazon | linux | libssh2-debuginfo | p-cpe:/a:amazon:linux:libssh2-debuginfo |
amazon | linux | libssh2-devel | p-cpe:/a:amazon:linux:libssh2-devel |
amazon | linux | libssh2-docs | p-cpe:/a:amazon:linux:libssh2-docs |
amazon | linux | 2 | cpe:/o:amazon:linux:2 |