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
AI Score
Confidence
High
EPSS
Percentile
56.0%
The version of Cisco IOS XE software running on the remote Cisco 1000 Series Aggregation Services Router (ASR) is affected by a denial of service vulnerability in the Embedded Services Processor (ESP) due to a flaw in handling the reassembly of fragmented IPv4 or IPv6 packets.
A remote, unauthenticated attacker, by sending a crafted sequence of fragmented packets, can exploit this vulnerability to cause the ESP to crash, leading to a reload of the affected platform.
#
# (C) Tenable Network Security, Inc.
#
include("compat.inc");
if (description)
{
script_id(85255);
script_version("1.9");
script_set_attribute(attribute:"plugin_modification_date", value:"2024/05/03");
script_cve_id("CVE-2015-4291");
script_xref(name:"CISCO-BUG-ID", value:"CSCtd72617");
script_xref(name:"CISCO-SA", value:"cisco-sa-20150730-asr1k");
script_name(english:"Cisco IOS XE Software for 1000 Series Aggregation Services Routers Fragmented Packet DoS");
script_summary(english:"Checks the IOS XE version.");
script_set_attribute(attribute:"synopsis", value:
"The remote device is missing a vendor-supplied security patch.");
script_set_attribute(attribute:"description", value:
"The version of Cisco IOS XE software running on the remote Cisco 1000
Series Aggregation Services Router (ASR) is affected by a denial of
service vulnerability in the Embedded Services Processor (ESP) due to
a flaw in handling the reassembly of fragmented IPv4 or IPv6 packets.
A remote, unauthenticated attacker, by sending a crafted sequence of
fragmented packets, can exploit this vulnerability to cause the ESP to
crash, leading to a reload of the affected platform.");
script_set_attribute(attribute:"see_also", value:"https://tools.cisco.com/bugsearch/bug/CSCtd72617");
# https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20150730-asr1k
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?ad3007fa");
script_set_attribute(attribute:"see_also", value:"https://tools.cisco.com/security/center/viewAlert.x?alertId=40212");
script_set_attribute(attribute:"solution", value:
"Apply the relevant patch referenced in the Cisco Security Advisory.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C");
script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
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:"2015/07/30");
script_set_attribute(attribute:"patch_publication_date", value:"2015/07/30");
script_set_attribute(attribute:"plugin_publication_date", value:"2015/08/06");
script_set_attribute(attribute:"plugin_type", value:"combined");
script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:ios_xe");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"CISCO");
script_copyright(english:"This script is Copyright (C) 2015-2024 Tenable Network Security, Inc.");
script_dependencies("cisco_ios_xe_version.nasl");
script_require_keys("Host/Cisco/IOS-XE/Version", "Host/Cisco/IOS-XE/Model");
exit(0);
}
include("audit.inc");
include("global_settings.inc");
include("misc_func.inc");
# Check model
model = get_kb_item_or_exit("Host/Cisco/IOS-XE/Model");
if (('ASR1k' >!< model && model !~ "^ASR\s*10[0-9][0-9]($|[^0-9])"))
audit(AUDIT_DEVICE_NOT_VULN, "Cisco " + model);
version = get_kb_item_or_exit("Host/Cisco/IOS-XE/Version");
fix = NULL;
if (version =~ "^2\.4\.[0-2]([^0-9]|$)")
fix = "2.4.3";
else if (version =~ "^2\.[1-3]([^0-9]|$)" || version =~ "^2\.5\.0([^0-9]|$)")
fix = "2.5.1";
if (isnull(fix)) audit(AUDIT_INST_VER_NOT_VULN, "Cisco IOS XE", version);
if (report_verbosity > 0)
{
report =
'\n Cisco bug ID : CSCtd72617' +
'\n Model : ' + model +
'\n Installed release : ' + version +
'\n Fixed release : ' + fix +
'\n';
security_hole(port:0, extra:report);
}
else security_hole(0);