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.

The SRX flowd process, responsible for packet forwarding, may crash and restart when processing specific multicast packets. By continuously sending the specific multicast packets, an attacker can repeatedly crash the flowd process causing a sustained Denial of Service. This issue affects Juniper Networks Junos OS on SRX Series: 12.3X48 versions prior to 12.3X48-D90; 15.1X49 versions prior to 15.1X49-D180; 17.3 versions; 17.4 versions prior to 17.4R2-S5, 17.4R3; 18.1 versions prior to 18.1R3-S6; 18.2 versions prior to 18.2R2-S4, 18.2R3; 18.3 versions prior to 18.3R2-S1, 18.3R3; 18.4 versions prior to 18.4R2; 19.1 versions prior to 19.1R1-S1, 19.1R2.

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.

SSL-Proxy feature on SRX devices fails to handle a hardware resource limitation which can be exploited by remote SSL/TLS servers to crash the flowd daemon. Repeated crashes of the flowd daemon can result in an extended denial of service condition. For this issue to occur, clients protected by the SRX device must initiate a connection to the malicious server. This issue affects: Juniper Networks Junos OS on SRX5000 Series: 12.3X48 versions prior to 12.3X48-D85; 15.1X49 versions prior to 15.1X49-D180; 17.3 versions prior to 17.3R3-S7; 17.4 versions prior to 17.4R2-S6, 17.4R3; 18.1 versions prior to 18.1R3-S8; 18.2 versions prior to 18.2R3; 18.3 versions prior to 18.3R2; 18.4 versions prior to 18.4R2; 19.1 versions prior to 19.1R2.

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.