5 Medium
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.132 Low
EPSS
Percentile
95.6%
Updated ypserv packages fixing a denial of service vulnerability are now available.
The ypserv package contains the Network Information Service (NIS) server.
A vulnerability has been discovered in the ypserv NIS server prior to version 2.7. If a malicious client queries ypserv via TCP and subsequently ignores the server’s response, ypserv will block attempting to send the reply. This results in ypserv failing to respond to other client requests.
Versions 2.7 and above of ypserv have been altered to fork a child for each client request, thus preventing any one request from causing the server to block.
Red Hat recommends that users of NIS upgrade to these packages, which contain version 2.8.0 of ypserv and are therefore not vulnerable to this issue.
#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Red Hat Security Advisory RHSA-2003:201. The text
# itself is copyright (C) Red Hat, Inc.
#
include('deprecated_nasl_level.inc');
include('compat.inc');
if (description)
{
script_id(12404);
script_version("1.26");
script_set_attribute(attribute:"plugin_modification_date", value:"2021/01/14");
script_cve_id("CVE-2003-0251");
script_xref(name:"RHSA", value:"2003:201");
script_name(english:"RHEL 2.1 : ypserv (RHSA-2003:201)");
script_summary(english:"Checks the rpm output for the updated package");
script_set_attribute(
attribute:"synopsis",
value:"The remote Red Hat host is missing a security update."
);
script_set_attribute(
attribute:"description",
value:
"Updated ypserv packages fixing a denial of service vulnerability are
now available.
The ypserv package contains the Network Information Service (NIS)
server.
A vulnerability has been discovered in the ypserv NIS server prior to
version 2.7. If a malicious client queries ypserv via TCP and
subsequently ignores the server's response, ypserv will block
attempting to send the reply. This results in ypserv failing to
respond to other client requests.
Versions 2.7 and above of ypserv have been altered to fork a child for
each client request, thus preventing any one request from causing the
server to block.
Red Hat recommends that users of NIS upgrade to these packages, which
contain version 2.8.0 of ypserv and are therefore not vulnerable to
this issue."
);
script_set_attribute(
attribute:"see_also",
value:"https://access.redhat.com/security/cve/cve-2003-0251"
);
script_set_attribute(
attribute:"see_also",
value:"http://www.linux-nis.org/nis/ypserv/ChangeLog"
);
script_set_attribute(
attribute:"see_also",
value:"https://access.redhat.com/errata/RHSA-2003:201"
);
script_set_attribute(
attribute:"solution",
value:"Update the affected ypserv package."
);
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:ypserv");
script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:2.1");
script_set_attribute(attribute:"vuln_publication_date", value:"2003/07/24");
script_set_attribute(attribute:"patch_publication_date", value:"2003/06/25");
script_set_attribute(attribute:"plugin_publication_date", value:"2004/07/06");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_copyright(english:"This script is Copyright (C) 2004-2021 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_family(english:"Red Hat Local Security Checks");
script_dependencies("ssh_get_info.nasl");
script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list", "Host/cpu");
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) || "Red Hat" >!< release) audit(AUDIT_OS_NOT, "Red Hat");
os_ver = pregmatch(pattern: "Red Hat Enterprise Linux.*release ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Red Hat");
os_ver = os_ver[1];
if (! preg(pattern:"^2\.1([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Red Hat 2.1", "Red Hat " + os_ver);
if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);
cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$" && "s390" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Red Hat", cpu);
if (cpu !~ "^i[3-6]86$") audit(AUDIT_ARCH_NOT, "i386", cpu);
yum_updateinfo = get_kb_item("Host/RedHat/yum-updateinfo");
if (!empty_or_null(yum_updateinfo))
{
rhsa = "RHSA-2003:201";
yum_report = redhat_generate_yum_updateinfo_report(rhsa:rhsa);
if (!empty_or_null(yum_report))
{
security_report_v4(
port : 0,
severity : SECURITY_WARNING,
extra : yum_report
);
exit(0);
}
else
{
audit_message = "affected by Red Hat security advisory " + rhsa;
audit(AUDIT_OS_NOT, audit_message);
}
}
else
{
flag = 0;
if (rpm_check(release:"RHEL2.1", cpu:"i386", reference:"ypserv-2.8-0.AS21E")) flag++;
if (flag)
{
security_report_v4(
port : 0,
severity : SECURITY_WARNING,
extra : rpm_report_get() + redhat_report_package_caveat()
);
exit(0);
}
else
{
tested = pkg_tests_get();
if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
else audit(AUDIT_PACKAGE_NOT_INSTALLED, "ypserv");
}
}
Vendor | Product | Version | CPE |
---|---|---|---|
redhat | enterprise_linux | ypserv | p-cpe:/a:redhat:enterprise_linux:ypserv |
redhat | enterprise_linux | 2.1 | cpe:/o:redhat:enterprise_linux:2.1 |