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
EPSS
Percentile
99.9%
Security Fix(es) :
An integer overflow flaw 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 (DoS). (CVE-2019-11477)
kernel: Double free in lib/idr.c (CVE-2019-3896)
Kernel: tcp: excessive resource consumption while processing SACK blocks allows remote denial of service (CVE-2019-11478)
Kernel: tcp: excessive resource consumption for TCP connections with low MSS allows remote denial of service (CVE-2019-11479)
Bug Fix(es) :
MDS mitigations not enabled on Intel Skylake CPUs
kernel does not disable SMT with mds=full,nosmt
md_clear flag missing from /proc/cpuinfo
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text is (C) Scientific Linux.
#
include("compat.inc");
if (description)
{
script_id(125980);
script_version("1.7");
script_set_attribute(attribute:"plugin_modification_date", value:"2022/12/06");
script_cve_id("CVE-2019-11477", "CVE-2019-11478", "CVE-2019-11479", "CVE-2019-3896");
script_xref(name:"CEA-ID", value:"CEA-2019-0456");
script_name(english:"Scientific Linux Security Update : kernel on SL6.x i386/x86_64 (20190617) (SACK Panic) (SACK Slowness)");
script_summary(english:"Checks rpm output for the updated packages");
script_set_attribute(
attribute:"synopsis",
value:
"The remote Scientific Linux host is missing one or more security
updates."
);
script_set_attribute(
attribute:"description",
value:
"Security Fix(es) :
- An integer overflow flaw 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 (DoS). (CVE-2019-11477)
- kernel: Double free in lib/idr.c (CVE-2019-3896)
- Kernel: tcp: excessive resource consumption while
processing SACK blocks allows remote denial of service
(CVE-2019-11478)
- Kernel: tcp: excessive resource consumption for TCP
connections with low MSS allows remote denial of service
(CVE-2019-11479)
Bug Fix(es) :
- MDS mitigations not enabled on Intel Skylake CPUs
- kernel does not disable SMT with mds=full,nosmt
- md_clear flag missing from /proc/cpuinfo"
);
# https://listserv.fnal.gov/scripts/wa.exe?A2=ind1906&L=SCIENTIFIC-LINUX-ERRATA&P=1368
script_set_attribute(
attribute:"see_also",
value:"http://www.nessus.org/u?95793eee"
);
script_set_attribute(attribute:"solution", value:"Update the affected packages.");
script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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-2019-3896");
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:fermilab:scientific_linux:kernel");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:kernel-abi-whitelists");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:kernel-debug");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:kernel-debug-debuginfo");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:kernel-debug-devel");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:kernel-debuginfo");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:kernel-debuginfo-common-i686");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:kernel-debuginfo-common-x86_64");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:kernel-devel");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:kernel-doc");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:kernel-firmware");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:kernel-headers");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:perf");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:perf-debuginfo");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:python-perf");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fermilab:scientific_linux:python-perf-debuginfo");
script_set_attribute(attribute:"cpe", value:"x-cpe:/o:fermilab:scientific_linux");
script_set_attribute(attribute:"vuln_publication_date", value:"2019/06/19");
script_set_attribute(attribute:"patch_publication_date", value:"2019/06/17");
script_set_attribute(attribute:"plugin_publication_date", value:"2019/06/18");
script_set_attribute(attribute:"in_the_news", value:"true");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_copyright(english:"This script is Copyright (C) 2019-2022 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_family(english:"Scientific Linux Local Security Checks");
script_dependencies("ssh_get_info.nasl");
script_require_keys("Host/local_checks_enabled", "Host/cpu", "Host/RedHat/release", "Host/RedHat/rpm-list");
exit(0);
}
include("audit.inc");
include("global_settings.inc");
include("misc_func.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) || "Scientific Linux " >!< release) audit(AUDIT_HOST_NOT, "running Scientific Linux");
os_ver = pregmatch(pattern: "Scientific Linux.*release ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Scientific Linux");
os_ver = os_ver[1];
if (! preg(pattern:"^6([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Scientific Linux 6.x", "Scientific Linux " + os_ver);
if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);
cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if (cpu >!< "x86_64" && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Scientific Linux", cpu);
flag = 0;
if (rpm_check(release:"SL6", reference:"kernel-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"kernel-abi-whitelists-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"kernel-debug-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"kernel-debug-debuginfo-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"kernel-debug-devel-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"kernel-debuginfo-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"kernel-debuginfo-common-i686-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", cpu:"x86_64", reference:"kernel-debuginfo-common-x86_64-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"kernel-devel-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"kernel-doc-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"kernel-firmware-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"kernel-headers-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"perf-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"perf-debuginfo-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"python-perf-2.6.32-754.15.3.el6")) flag++;
if (rpm_check(release:"SL6", reference:"python-perf-debuginfo-2.6.32-754.15.3.el6")) flag++;
if (flag)
{
security_report_v4(
port : 0,
severity : SECURITY_HOLE,
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, "kernel / kernel-abi-whitelists / kernel-debug / etc");
}
Vendor | Product | Version | CPE |
---|---|---|---|
fermilab | scientific_linux | kernel-debug | p-cpe:/a:fermilab:scientific_linux:kernel-debug |
fermilab | scientific_linux | kernel-debuginfo | p-cpe:/a:fermilab:scientific_linux:kernel-debuginfo |
fermilab | scientific_linux | kernel-debuginfo-common-i686 | p-cpe:/a:fermilab:scientific_linux:kernel-debuginfo-common-i686 |
fermilab | scientific_linux | kernel-doc | p-cpe:/a:fermilab:scientific_linux:kernel-doc |
fermilab | scientific_linux | x-cpe:/o:fermilab:scientific_linux | |
fermilab | scientific_linux | kernel-debuginfo-common-x86_64 | p-cpe:/a:fermilab:scientific_linux:kernel-debuginfo-common-x86_64 |
fermilab | scientific_linux | python-perf-debuginfo | p-cpe:/a:fermilab:scientific_linux:python-perf-debuginfo |
fermilab | scientific_linux | kernel-debug-devel | p-cpe:/a:fermilab:scientific_linux:kernel-debug-devel |
fermilab | scientific_linux | kernel-devel | p-cpe:/a:fermilab:scientific_linux:kernel-devel |
fermilab | scientific_linux | kernel-headers | p-cpe:/a:fermilab:scientific_linux:kernel-headers |
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
EPSS
Percentile
99.9%