According to its SIP banner, the version of Asterisk running on the remote host is affected by the following vulnerabilities :
An information disclosure vulnerability, known as BEAST, exists in the SSL 3.0 and TLS 1.0 protocols due to a flaw in the way the initialization vector (IV) is selected when operating in cipher-block chaining (CBC) modes. A man-in-the-middle attacker can exploit this to obtain plaintext HTTP header data, by using a blockwise chosen-boundary attack (BCBA) on an HTTPS session, in conjunction with JavaScript code that uses the HTML5 WebSocket API, the Java URLConnection API, or the Silverlight WebClient API. (CVE-2011-3389)
An integer overflow condition exists in sip.conf due to improper validation of user-supplied input when handling ‘timert1’ values. A remote attacker can exploit this to cause a denial of service.
An unspecified flaw exists due to improper handling of FAT data in UDPTL packets. A remote attacker can exploit this to cause a denial of service.
Note that Nessus has not tested for these issues but has instead relied only on the application’s self-reported version number.
#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#
include('deprecated_nasl_level.inc');
include('compat.inc');
if (description)
{
script_id(88715);
script_version("1.14");
script_set_attribute(attribute:"plugin_modification_date", value:"2022/12/05");
script_cve_id("CVE-2011-3389");
script_bugtraq_id(
49778,
82651,
82656,
82670
);
script_xref(name:"CERT", value:"864643");
script_xref(name:"CEA-ID", value:"CEA-2019-0547");
script_name(english:"Asterisk Multiple Vulnerabilities (AST-2016-001 - AST-2016-003) (BEAST)");
script_set_attribute(attribute:"synopsis", value:
"A telephony application running on the remote host is affected by
multiple vulnerabilities.");
script_set_attribute(attribute:"description", value:
"According to its SIP banner, the version of Asterisk running on the
remote host is affected by the following vulnerabilities :
- An information disclosure vulnerability, known as BEAST,
exists in the SSL 3.0 and TLS 1.0 protocols due to a
flaw in the way the initialization vector (IV) is
selected when operating in cipher-block chaining (CBC)
modes. A man-in-the-middle attacker can exploit this
to obtain plaintext HTTP header data, by using a
blockwise chosen-boundary attack (BCBA) on an HTTPS
session, in conjunction with JavaScript code that uses
the HTML5 WebSocket API, the Java URLConnection API,
or the Silverlight WebClient API. (CVE-2011-3389)
- An integer overflow condition exists in sip.conf due to
improper validation of user-supplied input when handling
'timert1' values. A remote attacker can exploit this to
cause a denial of service.
- An unspecified flaw exists due to improper handling of
FAT data in UDPTL packets. A remote attacker can exploit
this to cause a denial of service.
Note that Nessus has not tested for these issues but has instead
relied only on the application's self-reported version number.");
script_set_attribute(attribute:"see_also", value:"http://downloads.asterisk.org/pub/security/AST-2016-001.html");
script_set_attribute(attribute:"see_also", value:"http://downloads.asterisk.org/pub/security/AST-2016-002.html");
script_set_attribute(attribute:"see_also", value:"http://downloads.asterisk.org/pub/security/AST-2016-003.html");
script_set_attribute(attribute:"see_also", value:"https://www.imperialviolet.org/2011/09/23/chromeandbeast.html");
script_set_attribute(attribute:"solution", value:
"Upgrade to Asterisk version 11.21.1 / 13.7.1 / 11.6-cert12 /
13.1-cert3. Alternatively, apply the appropriate patch referenced in
the vendor advisories.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N");
script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2011-3389");
script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
script_set_attribute(attribute:"exploit_available", value:"false");
script_set_attribute(attribute:"in_the_news", value:"true");
script_set_attribute(attribute:"vuln_publication_date", value:"2011/08/31");
script_set_attribute(attribute:"patch_publication_date", value:"2016/02/03");
script_set_attribute(attribute:"plugin_publication_date", value:"2016/02/12");
script_set_attribute(attribute:"potential_vulnerability", value:"true");
script_set_attribute(attribute:"plugin_type", value:"remote");
script_set_attribute(attribute:"cpe", value:"cpe:/a:digium:asterisk");
script_set_attribute(attribute:"thorough_tests", value:"true");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Misc.");
script_copyright(english:"This script is Copyright (C) 2016-2022 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("asterisk_detection.nasl");
script_require_keys("asterisk/sip_detected", "Settings/ParanoidReport");
exit(0);
}
include("audit.inc");
include("global_settings.inc");
include("misc_func.inc");
get_kb_item_or_exit("asterisk/sip_detected");
asterisk_kbs = get_kb_list_or_exit("sip/asterisk/*/version");
if (report_paranoia < 2) audit(AUDIT_PARANOID);
is_vuln = FALSE;
not_vuln_installs = make_list();
errors = make_list();
foreach kb_name (keys(asterisk_kbs))
{
vulnerable = 0;
patch_only = FALSE;
matches = eregmatch(pattern:"/(udp|tcp)/([0-9]+)/version", string:kb_name);
if (isnull(matches))
{
errors = make_list(errors, "Unexpected error parsing port number from '"+kb_name+"'.");
continue;
}
proto = matches[1];
port = matches[2];
version = asterisk_kbs[kb_name];
if (version == 'unknown')
{
errors = make_list(errors, "Unable to obtain version of install on " + proto + "/" + port + ".");
continue;
}
banner = get_kb_item("sip/asterisk/" + proto + "/" + port + "/source");
if (!banner)
{
# We have version but banner is missing;
# log error and use in version-check though.
errors = make_list(errors, "KB item 'sip/asterisk/" + proto + "/" + port + "/source' is missing.");
banner = 'unknown';
}
# Open Source 1.8.x
# Patch does not change version.
if (version =~ "^1\.8([^0-9]|$)" && "cert" >!< tolower(version))
{
fixed = "See vendor for patch information.";
patch_only = TRUE;
}
# Open Source 11.x
if (version =~ "^11([^0-9]|$)" && "cert" >!< tolower(version))
{
fixed = "11.21.1";
vulnerable = ver_compare(ver:version, fix:fixed, app:"asterisk");
}
# Open Source 12.x
# Patch does not change version
else if (version =~ "^12([^0-9]|$)" && "cert" >!< tolower(version))
{
fixed = "See vendor for patch information.";
patch_only = TRUE;
}
# Open Source 13.x
else if (version =~ "^13([^0-9]|$)" && "cert" >!< tolower(version))
{
fixed = "13.7.1";
vulnerable = ver_compare(ver:version, fix:fixed, app:"asterisk");
}
# Asterisk Certified 1.8.28-certx
# Patch does not change version.
else if (version =~ "^1\.8\.28([^0-9])" && "cert" >< tolower(version))
{
fixed = "See vendor for patch information.";
patch_only = TRUE;
}
# Asterisk Certified 11.6-certx
else if (version =~ "^11\.6([^0-9])" && "cert" >< tolower(version))
{
fixed = "11.6-cert12";
vulnerable = ver_compare(ver:version, fix:fixed, app:"asterisk");
}
# Asterisk Certified 13.1-certx < 13.1-cert2
else if (version =~ "^13\.1([^0-9])" && "cert" >< tolower(version))
{
fixed = "13.1-cert3";
vulnerable = ver_compare(ver:version, fix:fixed, app:"asterisk");
}
if (vulnerable < 0 || patch_only == TRUE)
{
is_vuln = TRUE;
if (report_verbosity > 0)
{
report =
'\n Version source : ' + banner +
'\n Installed version : ' + version +
'\n Fixed version : ' + fixed +
'\n';
security_warning(port:port, proto:proto, extra:report);
}
else security_warning(port:port, proto:proto);
}
else not_vuln_installs = make_list(not_vuln_installs, version + " on port " + proto + "/" + port);
}
if (max_index(errors))
{
if (max_index(errors) == 1) errmsg = errors[0];
else errmsg = 'Errors were encountered verifying installs : \n ' + join(errors, sep:'\n ');
exit(1, errmsg);
}
else
{
installs = max_index(not_vuln_installs);
if (installs == 0)
{
if (is_vuln) exit(0);
else audit(AUDIT_NOT_INST, "Asterisk");
}
else audit(AUDIT_INST_VER_NOT_VULN, "Asterisk", not_vuln_installs);
}