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
7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
0.001 Low
EPSS
Percentile
45.6%
According to its self-reported version, the remote Juniper Junos OS device is affected by a denial of service (DoS) vulnerability. When a device running Juniper Networks Junos OS with MPC7, MPC8, or MPC9 line cards installed and the system is configured for inline IP reassembly, used by L2TP, MAP-E, GRE, and IPIP, the packet forwarding engine (PFE) will become disabled upon receipt of small fragments requiring reassembly. By continuously sending fragmented packets that cannot be reassembled, an attacker can repeatedly disable the PFE causing a sustained DoS.
Note that Nessus has not tested for this issue but has instead relied only on the application’s self-reported version number.
#TRUSTED 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
#
# (C) Tenable Network Security, Inc.
#
include('compat.inc');
if (description)
{
script_id(138908);
script_version("1.10");
script_set_attribute(attribute:"plugin_modification_date", value:"2021/06/03");
script_cve_id("CVE-2020-1649");
script_xref(name:"JSA", value:"JSA11036");
script_xref(name:"IAVA", value:"2020-A-0320-S");
script_name(english:"Juniper Junos MX Series PFE Small Packet DoS (JSA11036)");
script_set_attribute(attribute:"synopsis", value:
"The remote device is missing a vendor-supplied security patch.");
script_set_attribute(attribute:"description", value:
"According to its self-reported version, the remote Juniper Junos OS device is affected by a denial of service (DoS)
vulnerability. When a device running Juniper Networks Junos OS with MPC7, MPC8, or MPC9 line cards installed and the
system is configured for inline IP reassembly, used by L2TP, MAP-E, GRE, and IPIP, the packet forwarding engine (PFE)
will become disabled upon receipt of small fragments requiring reassembly. By continuously sending fragmented packets
that cannot be reassembled, an attacker can repeatedly disable the PFE causing a sustained DoS.
Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
script_set_attribute(attribute:"see_also", value:"https://kb.juniper.net/JSA11036");
script_set_attribute(attribute:"solution", value:
"Apply the relevant Junos software release referenced in Juniper advisory JSA11036");
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:H");
script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2020-1649");
script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
script_set_attribute(attribute:"vuln_publication_date", value:"2020/07/08");
script_set_attribute(attribute:"patch_publication_date", value:"2020/07/08");
script_set_attribute(attribute:"plugin_publication_date", value:"2020/07/24");
script_set_attribute(attribute:"plugin_type", value:"combined");
script_set_attribute(attribute:"cpe", value:"cpe:/o:juniper:junos");
script_set_attribute(attribute:"stig_severity", value:"I");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Junos Local Security Checks");
script_copyright(english:"This script is Copyright (C) 2020-2021 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("junos_version.nasl");
script_require_keys("Host/Juniper/JUNOS/Version", "Host/Juniper/model");
exit(0);
}
include('junos.inc');
model = get_kb_item_or_exit('Host/Juniper/model');
if (model !~ '^MX')
audit(AUDIT_HOST_NOT, 'an affected model');
if (report_paranoia < 2)
audit(AUDIT_PARANOID);
ver = get_kb_item_or_exit('Host/Juniper/JUNOS/Version');
fixes = make_array();
fixes['17.2'] = '17.2R3-S4';
fixes['17.3'] = '17.3R3-S8';
if (ver =~ "^17\.4R3")
fixes['17.4'] = '17.4R3-S1';
else
fixes['17.4'] = '17.4R2-S9';
fixes['18.1'] = '18.1R3-S10';
if (ver =~ "^18\.2R3")
fixes['18.2'] = '18.2R3-S3';
else
fixes['18.2'] = '18.2R2-S6';
fixes['18.2X75'] = '18.2X75-D34';
if (ver =~ "^18\.3R3")
fixes['18.3'] = '18.3R3-S2';
else if (ver =~ "^18\.3R2")
fixes['18.3'] = '18.3R2-S4';
else
fixes['18.3'] = '18.3R1-S7';
if (ver =~ "^18\.4R1")
fixes['18.4'] = '18.4R1-S6';
else
fixes['18.4'] = '18.4R2-S4';
if (ver =~ "^19\.1R1")
fixes['19.1'] = '19.1R1-S4';
else
fixes['19.1'] = '19.1R2-S1';
fixes['19.2'] = '19.2R1-S3';
fixes['19.3'] = '19.3R2-S2';
fix = check_junos(ver:ver, fixes:fixes, exit_on_fail:TRUE);
report = get_report(ver:ver, fix:fix);
security_report_v4(severity:SECURITY_WARNING, port:0, extra:report);
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
7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
0.001 Low
EPSS
Percentile
45.6%