In a Dynamic Host Configuration Protocol version 6 (DHCPv6) environment, the jdhcpd daemon may crash and restart upon receipt of certain DHCPv6 solicit messages received from a DHCPv6 client. By continuously sending the same crafted packet, an attacker can repeatedly crash the jdhcpd process causing a sustained Denial of Service (DoS) to both IPv4 and IPv6 clients. Affected releases are Juniper Networks Junos OS: 15.1 versions prior to 15.1F6-S12, 15.1R7-S3; 15.1X49 versions prior to 15.1X49-D171, 15.1X49-D180; 15.1X53 versions prior to 15.1X53-D236, 15.1X53-D496; 16.1 versions prior to 16.1R3-S10, 16.1R7-S4; 16.2 versions prior to 16.2R2-S8; 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-S3; 17.4 versions prior to 17.4R1-S6, 17.4R2-S3; 18.1 versions prior to 18.1R2-S4, 18.1R3-S2; 18.2 versions prior to 18.2R2; 18.2X75 versions prior to 18.2X75-D30; 18.3 versions prior to 18.3R1-S2. This issue does not affect Junos OS releases prior to 15.1.

When "set system ports console insecure" is enabled, root login is disallowed for Junos OS as expected. However, the root password can be changed using "set system root-authentication plain-text-password" on systems booted from an OAM (Operations, Administration, and Maintenance) volume, leading to a possible administrative bypass with physical access to the console. OAM volumes (e.g. flash drives) are typically instantiated as /dev/gpt/oam, or /oam for short. Password recovery, changing the root password from a console, should not have been allowed from an insecure console. Affected releases are Juniper Networks Junos OS: 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-D496, 15.1X53-D68; 16.1 versions prior to 16.1R3-S10, 16.1R6-S6, 16.1R7-S3; 16.1X65 versions prior to 16.1X65-D49; 16.2 versions prior to 16.2R2-S8; 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-S3; 17.4 versions prior to 17.4R1-S6, 17.4R2-S2; 18.1 versions prior to 18.1R2-S4, 18.1R3-S3; 18.2 versions prior to 18.2R2; 18.2X75 versions prior to 18.2X75-D40; 18.3 versions prior to 18.3R1-S2. This issue does not affect Junos OS releases prior to 15.1.

When BGP tracing is enabled an incoming BGP message may cause the Junos OS routing protocol daemon (rpd) process to crash and restart. While rpd restarts after a crash, repeated crashes can result in an extended DoS condition. Affected releases are Juniper Networks Junos OS: 16.1 versions prior to 16.1R7-S4, 16.1R7-S5; 16.2 versions prior to 16.2R2-S9, 16.2R3; 17.1 versions prior to 17.1R3; 17.2 versions prior to 17.2R3-S1; 17.3 versions prior to 17.3R3-S3, 17.3R3-S4, 17.3R4; 17.4 versions prior to 17.4R1-S7, 17.4R2-S3, 17.4R2-S4, 17.4R3; 18.1 versions prior to 18.1R2-S4, 18.1R3-S4, 18.1R4; 18.2 versions prior to 18.2R2-S2, 18.2R2-S3, 18.2R3; 18.2X75 versions prior to 18.2X75-D40; 18.3 versions prior to 18.3R1-S3, 18.3R2; 18.4 versions prior to 18.4R1-S2, 18.4R2. This issue does not affect Junos releases prior to 16.1R1.

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.

An issue was discovered in Embedthis GoAhead before 4.0.1 and Appweb before 7.0.2. The server mishandles some HTTP request fields associated with time, which results in a NULL pointer dereference, as demonstrated by If-Modified-Since or If-Unmodified-Since with a month greater than 11.

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.

Embedthis Appweb before 4.6.6 and 5.x before 5.2.1 allows remote attackers to cause a denial of service (NULL pointer dereference) via a Range header with an empty value, as demonstrated by "Range: x=,".

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.