An Improper Check for Unusual or Exceptional Conditions in packet processing on the MS-MPC/MS-MIC utilized by Juniper Networks Junos OS allows a malicious attacker to send a specific packet, triggering the MS-MPC/MS-MIC to reset, causing a Denial of Service (DoS). Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue only affects specific versions of Juniper Networks Junos OS on MX Series: 17.3R3-S11; 17.4R2-S13; 17.4R3 prior to 17.4R3-S5; 18.1R3-S12; 18.2R2-S8, 18.2R3-S7, 18.2R3-S8; 18.3R3-S4; 18.4R3-S7; 19.1R3-S4, 19.1R3-S5; 19.2R1-S6; 19.3R3-S2; 19.4R2-S4, 19.4R2-S5; 19.4R3-S2; 20.1R2-S1; 20.2R2-S2, 20.2R2-S3, 20.2R3; 20.3R2, 20.3R2-S1; 20.4R1, 20.4R1-S1, 20.4R2; 21.1R1; This issue does not affect any version of Juniper Networks Junos OS prior to 15.1X49-D240;

When user-defined ARP Policer is configured and applied on one or more Aggregated Ethernet (AE) interface units, a Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability between the Device Control Daemon (DCD) and firewall process (dfwd) daemons of Juniper Networks Junos OS allows an attacker to bypass the user-defined ARP Policer. In this particular case the User ARP policer is replaced with default ARP policer. To review the desired ARP Policers and actual state one can run the command "show interfaces <> extensive" and review the output. See further details below. An example output is: show interfaces extensive | match policer Policer: Input: __default_arp_policer__ <<< incorrect if user ARP Policer was applied on an AE interface and the default ARP Policer is displayed Policer: Input: jtac-arp-ae5.317-inet-arp <<< correct if user ARP Policer was applied on an AE interface For all platforms, except SRX Series: This issue affects Juniper Networks Junos OS: All versions 5.6R1 and all later versions prior to 18.4 versions prior to 18.4R2-S9, 18.4R3-S9 with the exception of 15.1 versions 15.1R7-S10 and later versions; 19.4 versions prior to 19.4R3-S3; 20.1 versions prior to 20.1R3; 20.2 versions prior to 20.2R3-S2; 20.3 version 20.3R1 and later versions; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R2; This issue does not affect Juniper Networks Junos OS versions prior to 5.6R1. On SRX Series this issue affects Juniper Networks Junos OS: 18.4 versions prior to 18.4R2-S9, 18.4R3-S9; 19.4 versions prior to 19.4R3-S4; 20.1 versions prior to 20.1R3; 20.2 versions prior to 20.2R3-S2; 20.3 version 20.3R1 and later versions; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R2. This issue does not affect 18.4 versions prior to 18.4R1 on SRX Series. This issue does not affect Junos OS Evolved.

This issue is not applicable to NFX NextGen Software. On NFX Series devices the use of Hard-coded Credentials in Juniper Networks Junos OS allows an attacker to take over any instance of an NFX deployment. This issue is only exploitable through administrative interfaces. This issue affects: Juniper Networks Junos OS versions prior to 19.1R1 on NFX Series. No other platforms besides NFX Series devices are affected.

A Use of Hard-coded Credentials vulnerability exists in the NFX250 Series for the vSRX Virtual Network Function (VNF) instance, which allows an attacker to take control of the vSRX VNF instance if they have the ability to access an administrative service (e.g. SSH) on the VNF, either locally, or through the network. This issue only affects the NFX250 Series vSRX VNF. No other products or platforms are affected. This issue is only applicable to environments where the vSRX VNF root password has not been configured. This issue affects the Juniper Networks NFX250 Network Services Platform vSRX VNF instance on versions prior to 19.2R1.

utility.c in telnetd in netkit telnet through 0.17 allows remote attackers to execute arbitrary code via short writes or urgent data, because of a buffer overflow involving the netclear and nextitem functions.

If REST API is enabled, the Junos OS login credentials are vulnerable to brute force attacks. The high default connection limit of the REST API may allow an attacker to brute-force passwords using advanced scripting techniques. Additionally, administrators who do not enforce a strong password policy can increase the likelihood of success from brute force attacks. Affected releases are Juniper Networks Junos OS: 14.1X53 versions prior to 14.1X53-D49; 15.1 versions prior to 15.1F6-S12, 15.1R7-S3; 15.1X49 versions prior to 15.1X49-D160; 15.1X53 versions prior to 15.1X53-D236, 15.1X53-D495, 15.1X53-D591, 15.1X53-D69; 16.1 versions prior to 16.1R3-S10, 16.1R4-S12, 16.1R6-S6, 16.1R7-S3; 16.1X65 versions prior to 16.1X65-D49; 16.2 versions prior to 16.2R2-S7; 17.1 versions prior to 17.1R2-S10, 17.1R3; 17.2 versions prior to 17.2R1-S8, 17.2R3-S1; 17.3 versions prior to 17.3R3-S2; 17.4 versions prior to 17.4R1-S6, 17.4R2-S2; 18.1 versions prior to 18.1R2-S4, 18.1R3-S1; 18.2 versions prior to 18.2R1-S5; 18.2X75 versions prior to 18.2X75-D30; 18.3 versions prior to 18.3R1-S1.

A certain sequence of valid BGP or IPv6 BFD packets may trigger a stack based buffer overflow in the Junos OS Packet Forwarding Engine manager (FXPC) process on QFX5000 series, EX4300, EX4600 devices. This issue can result in a crash of the fxpc daemon or may potentially lead to remote code execution. Affected releases are Juniper Networks Junos OS on QFX 5000 series, EX4300, EX4600 are: 14.1X53; 15.1X53 versions prior to 15.1X53-D235; 17.1 versions prior to 17.1R3; 17.2 versions prior to 17.2R3; 17.3 versions prior to 17.3R3-S2, 17.3R4; 17.4 versions prior to 17.4R2-S1, 17.4R3; 18.1 versions prior to 18.1R3-S1, 18.1R4; 18.2 versions prior to 18.2R2; 18.2X75 versions prior to 18.2X75-D30; 18.3 versions prior to 18.3R2.

On EX2300 and EX3400 series, high disk I/O operations may disrupt the communication between the routing engine (RE) and the packet forwarding engine (PFE). In a virtual chassis (VC) deployment, this issue disrupts communication between the VC members. This issue does not affect other Junos platforms. Affected releases are Junos OS on EX2300 and EX3400 series: 15.1X53 versions prior to 15.1X53-D590; 18.1 versions prior to 18.1R2-S2, 18.1R3; 18.2 versions prior to 18.2R2.

Receipt of a specially crafted IPv6 exception packet may be able to trigger a kernel crash (vmcore), causing the device to reboot. The issue is specific to the processing of Broadband Edge (BBE) client route processing on MX Series subscriber management platforms, introduced by the Tomcat (Next Generation Subscriber Management) functionality in Junos OS 15.1. This issue affects no other platforms or configurations. Affected releases are Juniper Networks Junos OS: 15.1 versions prior to 15.1R7-S2, 15.1R8 on MX Series; 16.1 versions prior to 16.1R4-S11, 16.1R7-S2, 16.1R8 on MX Series; 16.2 versions prior to 16.2R3 on MX Series; 17.1 versions prior to 17.1R2-S9, 17.1R3 on MX Series; 17.2 versions prior to 17.2R2-S6, 17.2R3 on MX Series; 17.3 versions prior to 17.3R2-S4, 17.3R3-S2, 17.3R4 on MX Series; 17.4 versions prior to 17.4R2 on MX Series; 18.1 versions prior to 18.1R2-S3, 18.1R3 on MX Series; 18.2 versions prior to 18.2R1-S1, 18.2R2 on MX Series.

Receipt of a specially crafted DHCPv6 message destined to a Junos OS device configured as a DHCP server in a Broadband Edge (BBE) environment may result in a jdhcpd daemon crash. The daemon automatically restarts without intervention, but a continuous receipt of crafted DHCPv6 packets could leaded to an extended denial of service condition. This issue only affects Junos OS 15.1 and later. Earlier releases are unaffected by this issue. Devices are only vulnerable to the specially crafted DHCPv6 message if DHCP services are configured. Devices not configured to act as a DHCP server are not vulnerable to this issue. Affected releases are Juniper Networks Junos OS: 15.1 versions prior to 15.1R7-S2; 15.1X49 versions prior to 15.1X49-D160; 15.1X53 versions prior to 15.1X53-D235, 15.1X53-D495; 16.1 versions prior to 16.1R4-S11, 16.1R6-S6, 16.1R7-S2; 16.2 versions prior to 16.2R2-S7; 17.1 versions prior to 17.1R2-S9; 17.2 versions prior to 17.2R2-S6; 17.3 versions prior to 17.3R3-S1; 17.4 versions prior to 17.4R1-S5; 18.1 versions prior to 18.1R2-S3; 18.2 versions prior to 18.2R1-S2; 18.2X75 versions prior to 18.2X75-D20.

named in ISC BIND 9.x before 9.9.8-P4 and 9.10.x before 9.10.3-P4 allows remote attackers to cause a denial of service (assertion failure and daemon exit) via a crafted signature record for a DNAME record, related to db.c and resolver.c.

named in ISC BIND 9.x before 9.9.8-P4 and 9.10.x before 9.10.3-P4 does not properly handle DNAME records when parsing fetch reply messages, which allows remote attackers to cause a denial of service (assertion failure and daemon exit) via a malformed packet to the rndc (aka control channel) interface, related to alist.c and sexpr.c.

Memory leak in Juniper JUNOS Packet Forwarding Engine (PFE) allows remote attackers to cause a denial of service (memory exhaustion and device reboot) via certain IPv6 packets.

TCP, when using a large Window Size, makes it easier for remote attackers to guess sequence numbers and cause a denial of service (connection loss) to persistent TCP connections by repeatedly injecting a TCP RST packet, especially in protocols that use long-lived connections, such as BGP.