Vulnerabilities > CVE-2007-4323 - Remote Denial of Service vulnerability in Denyhosts 2.6

#%NASL_MIN_LEVEL 80502
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Gentoo Linux Security Advisory GLSA 200710-14.
#
# The advisory text is Copyright (C) 2001-2015 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(27049);
  script_version("1.13");
  script_cvs_date("Date: 2019/08/02 13:32:44");

  script_cve_id("CVE-2007-4323");
  script_xref(name:"GLSA", value:"200710-14");

  script_name(english:"GLSA-200710-14 : DenyHosts: Denial of Service");
  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-200710-14
(DenyHosts: Denial of Service)

    Daniel B. Cid discovered that DenyHosts used an incomplete regular
    expression to parse failed login attempts, a different issue than GLSA
    200701-01.
  
Impact :

    A remote unauthenticated attacker can add arbitrary hosts into the
    blacklist, including the 'all' keyword, by submitting specially crafted
    version identification strings to the SSH server banner. An attacker
    may use this to prevent legitimate users from accessing a host
    remotely.
  
Workaround :

    There is no known workaround at this time."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://security.gentoo.org/glsa/200710-14"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"All DenyHosts users should upgrade to the latest version:
    # emerge --sync
    # emerge --ask --oneshot --verbose '>=app-admin/denyhosts-2.6-r1'"
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:denyhosts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");

  script_set_attribute(attribute:"patch_publication_date", value:"2007/10/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2007/10/15");
  script_set_attribute(attribute:"vuln_publication_date", value:"2006/12/04");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2007-2019 Tenable Network Security, Inc.");
  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:"app-admin/denyhosts", unaffected:make_list("ge 2.6-r1"), vulnerable:make_list("lt 2.6-r1"))) 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, "DenyHosts");
}