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
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS
Percentile
54.2%
According to its self-reported version, the remote Cisco Web Security Appliance (WSA) is affected by a denial of service vulnerability in the web proxy framework due to improper processing of HTTPS packets.
An unauthenticated, remote attacker can exploit this vulnerability, via a malformed HTTPS request packet, to cause all requests traversing the WSA to be dropped, resulting in a denial of service condition.
#
# (C) Tenable Network Security, Inc.
#
include("compat.inc");
if (description)
{
script_id(89785);
script_version("1.8");
script_set_attribute(attribute:"plugin_modification_date", value:"2021/05/14");
script_cve_id("CVE-2016-1288");
script_bugtraq_id(83936);
script_xref(name:"CISCO-BUG-ID", value:"CSCuu24840");
script_xref(name:"CISCO-SA", value:"cisco-sa-20160302-wsa");
script_name(english:"Cisco Web Security Appliance HTTPS Packet Processing DoS (cisco-sa-20160302-wsa)");
script_summary(english:"Checks the WSA version.");
script_set_attribute(attribute:"synopsis", value:
"The remote security appliance is affected by a denial of service
vulnerability.");
script_set_attribute(attribute:"description", value:
"According to its self-reported version, the remote Cisco Web Security
Appliance (WSA) is affected by a denial of service vulnerability in
the web proxy framework due to improper processing of HTTPS packets.
An unauthenticated, remote attacker can exploit this vulnerability,
via a malformed HTTPS request packet, to cause all requests traversing
the WSA to be dropped, resulting in a denial of service condition.");
# https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160302-wsa
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?c99dc6df");
script_set_attribute(attribute:"solution", value:
"Upgrade to the relevant fixed version referenced in Cisco bug ID
CSCuu24840.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
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:L");
script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2016-1288");
script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
script_set_attribute(attribute:"exploit_available", value:"false");
script_set_attribute(attribute:"vuln_publication_date", value:"2016/03/02");
script_set_attribute(attribute:"patch_publication_date", value:"2016/03/02");
script_set_attribute(attribute:"plugin_publication_date", value:"2016/03/09");
script_set_attribute(attribute:"potential_vulnerability", value:"true");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"cpe:/h:cisco:web_security_appliance");
script_set_attribute(attribute:"cpe", value:"cpe:/a:cisco:web_security_appliance");
script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:web_security_appliance");
script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:asyncos");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"CISCO");
script_copyright(english:"This script is Copyright (C) 2016-2021 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("cisco_wsa_version.nasl");
script_require_keys("Settings/ParanoidReport", "Host/AsyncOS/Cisco Web Security Appliance/DisplayVersion", "Host/AsyncOS/Cisco Web Security Appliance/Version");
exit(0);
}
include("audit.inc");
include("global_settings.inc");
include("misc_func.inc");
display_ver = get_kb_item_or_exit('Host/AsyncOS/Cisco Web Security Appliance/DisplayVersion');
ver = get_kb_item_or_exit('Host/AsyncOS/Cisco Web Security Appliance/Version');
# Device has to have HTTPS proxying enabled
if (report_paranoia < 2)
audit(AUDIT_PARANOID);
display_fix = FALSE;
if (ver_compare(ver:ver, fix:"8.5.3.051", strict:FALSE) < 0)
display_fix = "8.5.3-051";
else if (ver =~ "^9\.0\." && ver_compare(ver:ver, fix:"9.0.0.485", strict:FALSE) < 0)
display_fix = "9.0.0-485";
if (!display_fix)
audit(AUDIT_INST_VER_NOT_VULN, 'Cisco WSA', display_ver);
report =
'\n Installed version : ' + display_ver +
'\n Fixed version : ' + display_fix +
'\n';
security_report_v4(port:0, severity:SECURITY_WARNING, extra:report);
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
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS
Percentile
54.2%