A Generation of Error Message Containing Sensitive Information vulnerability in the CLI of Juniper Networks Junos OS allows a locally authenticated attacker with low privileges to elevate these to the level of any other user logged in via J-Web at this time, potential leading to a full compromise of the device. This issue affects Juniper Networks Junos OS: All versions prior to 15.1R7-S11; 18.3 versions prior to 18.3R3-S6; 18.4 versions prior to 18.4R2-S9, 18.4R3-S10; 19.1 versions prior to 19.1R2-S3, 19.1R3-S7; 19.2 versions prior to 19.2R1-S8, 19.2R3-S4; 19.3 versions prior to 19.3R3-S4; 19.4 versions prior to 19.4R3-S6; 20.1 versions prior to 20.1R3-S2; 20.2 versions prior to 20.2R3-S3; 20.3 versions prior to 20.3R3-S1; 20.4 versions prior to 20.4R3-S1; 21.1 versions prior to 21.1R2-S1, 21.1R3; 21.2 versions prior to 21.2R1-S1, 21.2R2.

An Unchecked Error Condition vulnerability in the subscriber management daemon (smgd) of Juniper Networks Junos OS allows an unauthenticated adjacent attacker to cause a crash of and thereby a Denial of Service (DoS). In a subscriber management / broadband edge environment if a single session group configuration contains dual-stack and a pp0 interface, smgd will crash and restart every time a PPPoE client sends a specific message. This issue affects Juniper Networks Junos OS on MX Series: 16.1 version 16.1R1 and later versions prior to 18.4R3-S10; 19.1 versions prior to 19.1R2-S3, 19.1R3-S7; 19.2 versions prior to 19.2R1-S8, 19.2R3-S4; 19.3 versions prior to 19.3R3-S4; 19.4 versions prior to 19.4R3-S5; 20.1 versions prior to 20.1R3-S3; 20.2 versions prior to 20.2R3-S3; 20.3 versions prior to 20.3R3-S2; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R3; 21.2 versions prior to 21.2R2. This issue does not affect Juniper Networks Junos OS versions prior to 16.1R1.

A Protection Mechanism Failure vulnerability in the J-Web HTTP service of Juniper Networks Junos OS allows a remote unauthenticated attacker to perform Person-in-the-Middle (PitM) attacks against the device. This issue affects: Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S20; 15.1 versions prior to 15.1R7-S11; 18.3 versions prior to 18.3R3-S6; 18.4 versions prior to 18.4R3-S10; 19.1 versions prior to 19.1R3-S7; 19.2 versions prior to 19.2R3-S4; 19.3 versions prior to 19.3R3-S4; 19.4 versions prior to 19.4R3-S6; 20.1 versions prior to 20.1R3-S2; 20.2 versions prior to 20.2R3-S3; 20.3 versions prior to 20.3R3-S1; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R3; 21.2 versions prior to 21.2R2.

An Unchecked Return Value vulnerability in the authd (authentication daemon) of Juniper Networks Junos OS on MX Series configured for subscriber management / BBE allows an adjacent attacker to cause a crash by sending a specific username. This impacts authentication, authorization, and accounting (AAA) services on the MX devices and leads to a Denial of Service (DoS) condition. Continued receipted of these PPP login request will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS 15.1 versions prior to 15.1R7-S9; 17.3 versions prior to 17.3R3-S12; 17.4 versions prior to 17.4R3-S5; 18.1 versions prior to 18.1R3-S13; 18.2 versions prior to 18.2R3-S8; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R3-S9; 19.1 versions prior to 19.1R3-S6; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S3; 19.4 versions prior to 19.4R3-S3; 20.1 versions prior to 20.1R3; 20.2 versions prior to 20.2R3-S1; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R2.

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.