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.

When a device using Juniper Network's Dynamic Host Configuration Protocol Daemon (JDHCPD) process on Junos OS or Junos OS Evolved which is configured in relay mode it vulnerable to an attacker sending crafted IPv6 packets who may then arbitrarily execute commands as root on the target device. This issue affects IPv6 JDHCPD services. This issue affects: Juniper Networks Junos OS: 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D200; 15.1X53 versions prior to 15.1X53-D592; 16.1 versions prior to 16.1R7-S6; 16.2 versions prior to 16.2R2-S11; 17.1 versions prior to 17.1R2-S11, 17.1R3-S1; 17.2 versions prior to 17.2R2-S8, 17.2R3-S3; 17.3 versions prior to 17.3R3-S6; 17.4 versions prior to 17.4R2-S7, 17.4R3; 18.1 versions prior to 18.1R3-S8; 18.2 versions prior to 18.2R3-S2; 18.2X75 versions prior to 18.2X75-D60; 18.3 versions prior to 18.3R1-S6, 18.3R2-S2, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2-S3, 18.4R3; 19.1 versions prior to 19.1R1-S3, 19.1R2; 19.2 versions prior to 19.2R1-S3, 19.2R2*. and All versions prior to 19.3R1 on Junos OS Evolved. This issue do not affect versions of Junos OS prior to 15.1, or JDHCPD operating as a local server in non-relay mode.

Receipt of a specific MPLS or IPv6 packet on the core facing interface of an MX Series device configured for Broadband Edge (BBE) service may trigger a kernel crash (vmcore), causing the device to reboot. The issue is specific to the processing of packets destined to BBE clients connected to MX Series subscriber management platforms. This issue affects MX Series running Juniper Networks Junos OS: 17.2 versions starting from17.2R2-S6, 17.2R3 and later releases, prior to 17.2R3-S3; 17.3 versions starting from 17.3R2-S4, 17.3R3-S2 and later releases, prior to 17.3R2-S5, 17.3R3-S5; 17.4 versions starting from 17.4R2 and later releases, prior to 17.4R2-S7,17.4R3; 18.1 versions starting from 18.1R2-S3, 18.1R3 and later releases, prior to 18.1R3-S6; 18.2 versions starting from18.2R1-S1, 18.2R2 and later releases, prior to 18.2R3-S2; 18.2X75 versions prior to 18.2X75-D51, 18.2X75-D60; 18.3 versions prior to 18.3R3; 18.4 versions prior to 18.4R2; 19.1 versions prior to 19.1R1-S3, 19.1R2; 19.2 versions prior to 19.2R1-S2, 19.2R2. This issue does not affect Juniper Networks Junos OS versions prior to 17.2R2-S6.

A path traversal vulnerability in the Juniper Networks Junos OS device may allow an authenticated J-web user to read files with 'world' readable permission and delete files with 'world' writeable permission. This issue does not affect system files that can be accessed only by root user. This issue affects Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S13; 12.3X48 versions prior to 12.3X48-D85 on SRX Series; 14.1X53 versions prior to 14.1X53-D51; 15.1F6 versions prior to 15.1F6-S13; 15.1 versions prior to 15.1R7-S5; 15.1X49 versions prior to 15.1X49-D180 on SRX Series; 15.1X53 versions prior to 15.1X53-D238 on QFX5200/QFX5110 Series; 16.1 versions prior to 16.1R4-S13, 16.1R7-S5; 16.2 versions prior to 16.2R2-S10; 17.1 versions prior to 17.1R3-S1; 17.2 versions prior to 17.2R1-S9, 17.2R3-S2; 17.3 versions prior to 17.3R2-S5, 17.3R3-S5; 17.4 versions prior to 17.4R2-S9, 17.4R3; 18.1 versions prior to 18.1R3-S8; 18.2 versions prior to 18.2R3; 18.3 versions prior to 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R2; 19.1 versions prior to 19.1R1-S4, 19.1R2.

When a device using Juniper Network's Dynamic Host Configuration Protocol Daemon (JDHCPD) process on Junos OS or Junos OS Evolved which is configured in relay mode it vulnerable to an attacker sending crafted IPv4 packets who may then arbitrarily execute commands as root on the target device. This issue affects IPv4 JDHCPD services. This issue affects: Juniper Networks Junos OS: 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D200; 15.1X53 versions prior to 15.1X53-D592; 16.1 versions prior to 16.1R7-S6; 16.2 versions prior to 16.2R2-S11; 17.1 versions prior to 17.1R2-S11, 17.1R3-S1; 17.2 versions prior to 17.2R2-S8, 17.2R3-S3; 17.3 versions prior to 17.3R3-S6; 17.4 versions prior to 17.4R2-S7, 17.4R3; 18.1 versions prior to 18.1R3-S8; 18.2 versions prior to 18.2R3-S2; 18.2X75 versions prior to 18.2X75-D60; 18.3 versions prior to 18.3R1-S6, 18.3R2-S2, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2-S3, 18.4R3; 19.1 versions prior to 19.1R1-S3, 19.1R2; 19.2 versions prior to 19.2R1-S3, 19.2R2*. and All versions prior to 19.3R1 on Junos OS Evolved. This issue do not affect versions of Junos OS prior to 15.1, or JDHCPD operating as a local server in non-relay mode.

Specific IPv6 packets sent by clients processed by the Routing Engine (RE) are improperly handled. These IPv6 packets are designed to be blocked by the RE from egressing the RE. Instead, the RE allows these specific IPv6 packets to egress the RE, at which point a mbuf memory leak occurs within the Juniper Networks Junos OS device. This memory leak eventually leads to a kernel crash (vmcore), or the device hanging and requiring a power cycle to restore service, creating a Denial of Service (DoS) condition. During the time where mbufs are rising, yet not fully filled, some traffic from client devices may begin to be black holed. To be black holed, this traffic must match the condition where this traffic must be processed by the RE. Continued receipt and attempted egress of these specific IPv6 packets from the Routing Engine (RE) will create an extended Denial of Service (DoS) condition. Scenarios which have been observed are: 1. In a single chassis, single RE scenario, the device will hang without vmcore, or a vmcore may occur and then hang. In this scenario the device needs to be power cycled. 2. In a single chassis, dual RE scenario, the device master RE will fail over to the backup RE. In this scenario, the master and the backup REs need to be reset from time to time when they vmcore. There is no need to power cycle the device. 3. In a dual chassis, single RE scenario, the device will hang without vmcore, or a vmcore may occur and then hang. In this scenario, the two chassis' design relies upon some type of network level redundancy - VRRP, GRES, NSR, etc. - 3.a In a commanded switchover, where nonstop active routing (NSR) is enabled no session loss is observed. 4. In a dual chassis, dual chassis scenario, rely upon the RE to RE failover as stated in the second scenario. In the unlikely event that the device does not switch RE to RE gracefully, then the fallback position is to the network level services scenario in the third scenario. This issue affects: Juniper Networks Junos OS 16.1 versions prior to 16.1R7-S6; 16.1 version 16.1X70-D10 and later; 16.2 versions prior to 16.2R2-S11; 17.1 versions prior to 17.1R2-S11, 17.1R3-S1; 17.2 versions prior to 17.2R1-S9, 17.2R2-S8, 17.2R3-S3; 17.3 versions prior to 17.3R3-S6; 17.4 versions prior to 17.4R2-S9, 17.4R3; 18.1 versions prior to 18.1R3-S7; 18.2 versions prior to 18.2R3-S2; 18.2X75 versions prior to 18.2X75-D50, 18.2X75-D410; 18.3 versions prior to 18.3R1-S6, 18.3R2-S2, 18.3R3; 18.4 versions prior to 18.4R1-S6, 18.4R2-S2, 18.4R3; 19.1 versions prior to 19.1R1-S3, 19.1R2; 19.2 versions prior to 19.2R1-S2, 19.2R2. This issue does not affect releases prior to Junos OS 16.1R1.

When a device using Juniper Network's Dynamic Host Configuration Protocol Daemon (JDHCPD) process on Junos OS or Junos OS Evolved which is configured in relay mode it vulnerable to an attacker sending crafted IPv4 packets who may remotely take over the code execution of the JDHDCP process. This issue affect IPv4 JDHCPD services. This issue affects: Juniper Networks Junos OS: 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D200; 15.1X53 versions prior to 15.1X53-D592; 16.1 versions prior to 16.1R7-S6; 16.2 versions prior to 16.2R2-S11; 17.1 versions prior to 17.1R2-S11, 17.1R3-S1; 17.2 versions prior to 17.2R2-S8, 17.2R3-S3; 17.3 versions prior to 17.3R3-S6; 17.4 versions prior to 17.4R2-S7, 17.4R3; 18.1 versions prior to 18.1R3-S8; 18.2 versions prior to 18.2R3-S2; 18.2X75 versions prior to 18.2X75-D60; 18.3 versions prior to 18.3R1-S6, 18.3R2-S2, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2-S3, 18.4R3; 19.1 versions prior to 19.1R1-S3, 19.1R2; 19.2 versions prior to 19.2R1-S3, 19.2R2*. and All versions prior to 19.3R1 on Junos OS Evolved. This issue do not affect versions of Junos OS prior to 15.1, or JDHCPD operating as a local server in non-relay mode.

Certain types of malformed Path Computation Element Protocol (PCEP) packets when received and processed by a Juniper Networks Junos OS device serving as a Path Computation Client (PCC) in a PCEP environment using Juniper's path computational element protocol daemon (pccd) process allows an attacker to cause the pccd process to crash and generate a core file thereby causing a Denial of Service (DoS). Continued receipt of this family of malformed PCEP packets will cause an extended Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS: 15.1 versions prior to 15.1F6-S13, 15.1R7-S4; 15.1X49 versions prior to 15.1X49-D180 on SRX Series; 15.1X53 versions prior to 15.1X53-D238, 15.1X53-D496, 15.1X53-D592; 16.1 versions prior to 16.1R7-S4; 16.2 versions prior to 16.2R2-S9; 17.1 versions prior to 17.1R2-S11, 17.1R3; 17.2 versions prior to 17.2R1-S9; 17.2 version 17.2R2 and later prior to 17.2R3-S2; 17.3 versions prior to 17.3R3-S3; 17.4 versions prior to 17.4R2-S2, 17.4R3; 18.1 versions prior to 18.1R3-S2; 18.2 versions prior to 18.2R2-S6, 18.2R3; 18.2X75 versions prior to 18.2X75-D40; 18.3 versions prior to 18.3R2; 18.4 versions prior to 18.4R1-S2, 18.4R2. This issue does not affect releases of Junos OS prior to 15.1R1.

In a Point-to-Multipoint (P2MP) Label Switched Path (LSP) scenario, an uncontrolled resource consumption vulnerability in the Routing Protocol Daemon (RPD) in Juniper Networks Junos OS allows a specific SNMP request to trigger an infinite loop causing a high CPU usage Denial of Service (DoS) condition. This issue affects both SNMP over IPv4 and IPv6. This issue affects: Juniper Networks Junos OS: 12.3X48 versions prior to 12.3X48-D90; 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D200; 15.1X53 versions prior to 15.1X53-D238, 15.1X53-D592; 16.1 versions prior to 16.1R7-S5; 16.2 versions prior to 16.2R2-S11; 17.1 versions prior to 17.1R3-S1; 17.2 versions prior to 17.2R3-S2; 17.3 versions prior to 17.3R3-S7; 17.4 versions prior to 17.4R2-S4, 17.4R3; 18.1 versions prior to 18.1R3-S5; 18.2 versions prior to 18.2R3; 18.2X75 versions prior to 18.2X75-D50; 18.3 versions prior to 18.3R2; 18.4 versions prior to 18.4R2; 19.1 versions prior to 19.1R2.

On MX Series, when the SIP ALG is enabled, receipt of a certain malformed SIP packet may crash the MS-PIC component on MS-MIC or MS-MPC. By continuously sending a crafted SIP packet, an attacker can repeatedly bring down MS-PIC on MS-MIC/MS-MPC causing a sustained Denial of Service. This issue affects Juniper Networks Junos OS on MX Series: 16.1 versions prior to 16.1R7-S5; 16.2 versions prior to 16.2R2-S11; 17.1 versions prior to 17.1R3; 17.2 versions prior to 17.2R3-S3; 17.3 versions prior to 17.3R3-S6 ; 17.4 versions prior to 17.4R2-S8, 17.4R3; 18.1 versions prior to 18.1R3-S3; 18.2 versions prior to 18.2R3; 18.3 versions prior to 18.3R2; 18.4 versions prior to 18.4R2.

When an MX Series Broadband Remote Access Server (BRAS) is configured as a Broadband Network Gateway (BNG) with DHCPv6 enabled, jdhcpd might crash when receiving a specific crafted DHCP response message on a subscriber interface. The daemon automatically restarts without intervention, but continuous receipt of specific crafted DHCP messages will repeatedly crash jdhcpd, leading to an extended Denial of Service (DoS) condition. This issue only affects systems configured with DHCPv6 enabled. DHCPv4 is unaffected by this issue. This issue affects Juniper Networks Junos OS: 15.1 versions prior to 15.1R7-S5 on MX Series; 16.1 versions prior to 16.1R7-S5 on MX Series; 16.2 versions prior to 16.2R2-S10 on MX Series; 17.1 versions prior to 17.1R3-S1 on MX Series; 17.2 versions prior to 17.2R3-S2 on MX Series; 17.3 versions prior to 17.3R3-S6 on MX Series; 17.4 versions prior to 17.4R2-S5, 17.4R3 on MX Series; 18.1 versions prior to 18.1R3-S6 on MX Series; 18.2 versions prior to 18.2R2-S4, 18.2R3 on MX Series; 18.2X75 versions prior to 18.2X75-D50 on MX Series; 18.3 versions prior to 18.3R1-S5, 18.3R3 on MX Series; 18.4 versions prior to 18.4R2 on MX Series; 19.1 versions prior to 19.1R1-S2, 19.1R2 on MX Series.

A session fixation vulnerability in J-Web on Junos OS may allow an attacker to use social engineering techniques to fix and hijack a J-Web administrators web session and potentially gain administrative access to the device. This issue affects: Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S15 on EX Series; 12.3X48 versions prior to 12.3X48-D85 on SRX Series; 14.1X53 versions prior to 14.1X53-D51; 15.1 versions prior to 15.1F6-S13, 15.1R7-S5; 15.1X49 versions prior to 15.1X49-D180 on SRX Series; 15.1X53 versions prior to 15.1X53-D238; 16.1 versions prior to 16.1R4-S13, 16.1R7-S5; 16.2 versions prior to 16.2R2-S10; 17.1 versions prior to 17.1R3-S1; 17.2 versions prior to 17.2R2-S8, 17.2R3-S3; 17.3 versions prior to 17.3R3-S5; 17.4 versions prior to 17.4R2-S8, 17.4R3; 18.1 versions prior to 18.1R3-S8; 18.2 versions prior to 18.2R3; 18.3 versions prior to 18.3R3; 18.4 versions prior to 18.4R2; 19.1 versions prior to 19.1R1-S2, 19.1R2.

On EX4300 Series switches with TCAM optimization enabled, incoming multicast traffic matches an implicit loopback filter rule first, since it has high priority. This rule is meant for reserved multicast addresses 224.0.0.x, but incorrectly matches on 224.x.x.x. Due to this bug, when a firewall filter is applied on the loopback interface, other firewall filters might stop working for multicast traffic. The command 'show firewall filter' can be used to confirm whether the filter is working. This issue only affects the EX4300 switch. No other products or platforms are affected by this vulnerability. This issue affects: Juniper Networks Junos OS: 14.1X53 versions prior to 14.1X53-D51, 14.1X53-D115 on EX4300 Series; 17.1 versions prior to 17.1R3 on EX4300 Series; 17.2 versions prior to 17.2R3-S2 on EX4300 Series; 17.3 versions prior to 17.3R3-S3 on EX4300 Series; 17.4 versions prior to 17.4R2-S5, 17.4R3 on EX4300 Series; 18.1 versions prior to 18.1R3-S1 on EX4300 Series; 18.2 versions prior to 18.2R2 on EX4300 Series; 18.3 versions prior to 18.3R2 on EX4300 Series.