CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:N/I:N/A:C
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
AI Score
Confidence
High
EPSS
Percentile
99.9%
According to the version of the vzkernel package and the readykernel-patch installed, the Virtuozzo installation on the remote host is affected by the following vulnerabilities :
An integer overflow was found in the way the Linux kernel’s networking subsystem processed TCP Selective Acknowledgment (SACK) segments. While processing SACK segments, the Linux kernel’s socket buffer (SKB) data structure becomes fragmented. Each fragment is about TCP maximum segment size (MSS) bytes. To efficiently process SACK blocks, the Linux kernel merges multiple fragmented SKBs into one, potentially overflowing the variable holding the number of segments. A remote attacker could use this flaw to crash the Linux kernel by sending a crafted sequence of SACK segments on a TCP connection with small value of TCP MSS, resulting in a denial of service.
An excessive resource consumption issue was found in the way the Linux kernel’s networking subsystem processed TCP Selective Acknowledgment (SACK) segments.
While processing SACK segments, the Linux kernel’s socket buffer (SKB) data structure becomes fragmented, which leads to increased resource utilization to traverse and process these fragments as further SACK segments are received on the same TCP connection. A remote attacker could use this flaw to cause a denial of service (DoS) by sending a crafted sequence of SACK segments on a TCP connection.
Note that Tenable Network Security has extracted the preceding description block directly from the Virtuozzo security advisory.
Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#
include('deprecated_nasl_level.inc');
include('compat.inc');
if (description)
{
script_id(133456);
script_version("1.5");
script_set_attribute(attribute:"plugin_modification_date", value:"2024/03/28");
script_cve_id("CVE-2019-11477", "CVE-2019-11478");
script_xref(name:"CEA-ID", value:"CEA-2019-0456");
script_name(english:"Virtuozzo 7 : readykernel-patch (VZA-2019-050)");
script_set_attribute(attribute:"synopsis", value:
"The remote Virtuozzo host is missing a security update.");
script_set_attribute(attribute:"description", value:
"According to the version of the vzkernel package and the
readykernel-patch installed, the Virtuozzo installation on the remote
host is affected by the following vulnerabilities :
- An integer overflow was found in the way the Linux
kernel's networking subsystem processed TCP Selective
Acknowledgment (SACK) segments. While processing SACK
segments, the Linux kernel's socket buffer (SKB) data
structure becomes fragmented. Each fragment is about
TCP maximum segment size (MSS) bytes. To efficiently
process SACK blocks, the Linux kernel merges multiple
fragmented SKBs into one, potentially overflowing the
variable holding the number of segments. A remote
attacker could use this flaw to crash the Linux kernel
by sending a crafted sequence of SACK segments on a TCP
connection with small value of TCP MSS, resulting in a
denial of service.
- An excessive resource consumption issue was found in
the way the Linux kernel's networking subsystem
processed TCP Selective Acknowledgment (SACK) segments.
While processing SACK segments, the Linux kernel's
socket buffer (SKB) data structure becomes fragmented,
which leads to increased resource utilization to
traverse and process these fragments as further SACK
segments are received on the same TCP connection. A
remote attacker could use this flaw to cause a denial
of service (DoS) by sending a crafted sequence of SACK
segments on a TCP connection.
Note that Tenable Network Security has extracted the preceding
description block directly from the Virtuozzo security advisory.
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://virtuozzosupport.force.com/s/article/VZA-2019-050");
script_set_attribute(attribute:"see_also", value:"https://readykernel.com/patch/1572/");
script_set_attribute(attribute:"see_also", value:"https://readykernel.com/patch/1574/");
script_set_attribute(attribute:"see_also", value:"https://readykernel.com/patch/1576/");
script_set_attribute(attribute:"see_also", value:"https://readykernel.com/patch/1578/");
script_set_attribute(attribute:"see_also", value:"https://readykernel.com/patch/1579/");
script_set_attribute(attribute:"see_also", value:"https://readykernel.com/patch/1582/");
script_set_attribute(attribute:"see_also", value:"https://readykernel.com/patch/1583/");
script_set_attribute(attribute:"see_also", value:"https://readykernel.com/patch/1584/");
script_set_attribute(attribute:"see_also", value:"https://readykernel.com/patch/1587/");
script_set_attribute(attribute:"see_also", value:"https://readykernel.com/patch/1590/");
script_set_attribute(attribute:"solution", value:
"Update the readykernel patch.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C");
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:N/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-2019-11477");
script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2019-11478");
script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
script_set_attribute(attribute:"exploit_available", value:"false");
script_set_attribute(attribute:"patch_publication_date", value:"2019/06/20");
script_set_attribute(attribute:"plugin_publication_date", value:"2020/02/04");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:virtuozzo:virtuozzo:readykernel");
script_set_attribute(attribute:"cpe", value:"cpe:/o:virtuozzo:virtuozzo:7");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Virtuozzo Local Security Checks");
script_copyright(english:"This script is Copyright (C) 2020-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ssh_get_info.nasl");
script_require_keys("Host/local_checks_enabled", "Host/Virtuozzo/release", "Host/Virtuozzo/rpm-list", "Host/readykernel-info");
exit(0);
}
include("global_settings.inc");
include("readykernel.inc");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/Virtuozzo/release");
if (isnull(release) || "Virtuozzo" >!< release) audit(AUDIT_OS_NOT, "Virtuozzo");
os_ver = pregmatch(pattern: "Virtuozzo Linux release ([0-9]+\.[0-9])(\D|$)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Virtuozzo");
os_ver = os_ver[1];
if (! preg(pattern:"^7([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Virtuozzo 7.x", "Virtuozzo " + os_ver);
if (!get_kb_item("Host/Virtuozzo/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, "Virtuozzo", cpu);
rk_info = get_kb_item("Host/readykernel-info");
if (empty_or_null(rk_info)) audit(AUDIT_UNKNOWN_APP_VER, "Virtuozzo");
checks = make_list2(
make_array(
"kernel","vzkernel-3.10.0-693.11.6.vz7.40.4",
"patch","readykernel-patch-40.4-82.0-1.vl7"
),
make_array(
"kernel","vzkernel-3.10.0-693.17.1.vz7.43.10",
"patch","readykernel-patch-43.10-82.0-1.vl7"
),
make_array(
"kernel","vzkernel-3.10.0-693.21.1.vz7.46.7",
"patch","readykernel-patch-46.7-82.0-1.vl7"
),
make_array(
"kernel","vzkernel-3.10.0-693.21.1.vz7.48.2",
"patch","readykernel-patch-48.2-82.0-1.vl7"
),
make_array(
"kernel","vzkernel-3.10.0-862.9.1.vz7.63.3",
"patch","readykernel-patch-63.3-82.0-1.vl7"
),
make_array(
"kernel","vzkernel-3.10.0-862.11.6.vz7.64.7",
"patch","readykernel-patch-64.7-82.0-1.vl7"
),
make_array(
"kernel","vzkernel-3.10.0-862.20.2.vz7.73.24",
"patch","readykernel-patch-73.24-82.0-1.vl7"
),
make_array(
"kernel","vzkernel-3.10.0-862.20.2.vz7.73.29",
"patch","readykernel-patch-73.29-82.0-1.vl7"
),
make_array(
"kernel","vzkernel-3.10.0-957.10.1.vz7.85.17",
"patch","readykernel-patch-85.17-82.0-1.vl7"
),
make_array(
"kernel","vzkernel-3.10.0-957.12.2.vz7.86.2",
"patch","readykernel-patch-86.2-82.0-1.vl7"
)
);
readykernel_execute_checks(checks:checks, severity:SECURITY_HOLE, release:"Virtuozzo-7");
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-11477
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-11478
readykernel.com/patch/1572/
readykernel.com/patch/1574/
readykernel.com/patch/1576/
readykernel.com/patch/1578/
readykernel.com/patch/1579/
readykernel.com/patch/1582/
readykernel.com/patch/1583/
readykernel.com/patch/1584/
readykernel.com/patch/1587/
readykernel.com/patch/1590/
virtuozzosupport.force.com/s/article/VZA-2019-050
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:N/I:N/A:C
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
AI Score
Confidence
High
EPSS
Percentile
99.9%