Receipt of specially crafted UDP/IP packets over MPLS may be able to bypass a stateless firewall filter. The crafted UDP packets must be encapsulated and meet a very specific packet format to be classified in a way that bypasses IP firewall filter rules. The packets themselves do not cause a service interruption (e.g. RPD crash), but receipt of a high rate of UDP packets may be able to contribute to a denial of service attack. This issue only affects processing of transit UDP/IP packets over MPLS, received on an interface with MPLS enabled. TCP packet processing and non-MPLS encapsulated UDP packet processing are unaffected by this issue. Affected releases are Juniper Networks Junos OS: 12.1X46 versions prior to 12.1X46-D76; 12.3 versions prior to 12.3R12-S10; 12.3X48 versions prior to 12.3X48-D66, 12.3X48-D70; 14.1X53 versions prior to 14.1X53-D47; 15.1 versions prior to 15.1F6-S10, 15.1R4-S9, 15.1R6-S6, 15.1R7; 15.1X49 versions prior to 15.1X49-D131, 15.1X49-D140; 15.1X53 versions prior to 15.1X53-D59 on EX2300/EX3400; 15.1X53 versions prior to 15.1X53-D67 on QFX10K; 15.1X53 versions prior to 15.1X53-D233 on QFX5200/QFX5110; 15.1X53 versions prior to 15.1X53-D471, 15.1X53-D490 on NFX; 16.1 versions prior to 16.1R3-S8, 16.1R4-S9, 16.1R5-S4, 16.1R6-S3, 16.1R7; 16.2 versions prior to 16.2R1-S6, 16.2R2-S5, 16.2R3; 17.1 versions prior to 17.1R1-S7, 17.1R2-S7, 17.1R3; 17.2 versions prior to 17.2R1-S6, 17.2R2-S4, 17.2R3; 17.2X75 versions prior to 17.2X75-D100; 17.3 versions prior to 17.3R1-S4, 17.3R2-S2, 17.3R3; 17.4 versions prior to 17.4R1-S3, 17.4R2; 18.1 versions prior to 18.1R2; 18.2X75 versions prior to 18.2X75-D5.

Receipt of a specific MPLS packet may cause MPC7/8/9, PTX-FPC3 (FPC-P1, FPC-P2) line cards or PTX1K to crash and restart. By continuously sending specific MPLS packets, an attacker can repeatedly crash the line cards or PTX1K causing a sustained Denial of Service. Affected releases are Juniper Networks Junos OS with MPC7/8/9 or PTX-FPC3 (FPC-P1, FPC-P2) installed and PTX1K: 15.1F versions prior to 15.1F6-S10; 15.1 versions prior to 15.1R4-S9, 15.1R6-S6, 15.1R7; 16.1 versions prior to 16.1R3-S8, 16.1R4-S9, 16.1R5-S4, 16.1R6-S3, 16.1R7; 16.1X65 versions prior to 16.1X65-D46; 16.2 versions prior to 16.2R1-S6, 16.2R2-S5, 16.2R3; 17.1 versions prior to 17.1R1-S7, 17.1R2-S7, 17.1R3; 17.2 versions prior to 17.2R1-S4, 17.2R2-S4, 17.2R3; 17.2X75 versions prior to 17.2X75-D70, 17.2X75-D90; 17.3 versions prior to 17.3R1-S4, 17.3R2, 17.4 versions prior to 17.4R1-S2, 17.4R2. Refer to KB25385 for more information about PFE line cards.

While experiencing a broadcast storm, placing the fxp0 interface into promiscuous mode via the 'monitor traffic interface fxp0' can cause the system to crash and restart (vmcore). This issue only affects Junos OS 15.1 and later releases, and affects both single core and multi-core REs. Releases prior to Junos OS 15.1 are unaffected by this vulnerability. Affected releases are Juniper Networks Junos OS: 15.1 versions prior to 15.1F6-S11, 15.1R4-S9, 15.1R6-S6, 15.1R7; 15.1X49 versions prior to 15.1X49-D140; 15.1X53 versions prior to 15.1X53-D59 on EX2300/EX3400; 15.1X53 versions prior to 15.1X53-D67 on QFX10K; 15.1X53 versions prior to 15.1X53-D233 on QFX5200/QFX5110; 15.1X53 versions prior to 15.1X53-D471, 15.1X53-D490 on NFX; 16.1 versions prior to 16.1R3-S8, 16.1R5-S4, 16.1R6-S1, 16.1R7; 16.2 versions prior to 16.2R1-S6, 16.2R2-S5, 16.2R3; 17.1 versions prior to 17.1R1-S7, 17.1R2-S7, 17.1R3; 17.2 versions prior to 17.2R1-S6, 17.2R2-S4, 17.2R3; 17.2X75 versions prior to 17.2X75-D90, 17.2X75-D110; 17.3 versions prior to 17.3R1-S4, 17.3R2; 17.4 versions prior to 17.4R1-S3, 17.4R2.

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.