On Juniper Networks Junos OS devices, receipt of a malformed IPv6 packet may cause the system to crash and restart (vmcore). This issue can be trigged by a malformed IPv6 packet destined to the Routing Engine. An attacker can repeatedly send the offending packet resulting in an extended Denial of Service condition. Only IPv6 packets can trigger this issue. IPv4 packets cannot trigger this issue. This issue affects Juniper Networks Junos OS 18.4 versions prior to 18.4R2-S4, 18.4R3-S1; 19.1 versions prior to 19.1R2-S1, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2. This issue does not affect Juniper Networks Junos OS prior to 18.4R1.
The following software releases have been updated to resolve this specific issue: Junos OS 18.4R2-S4, 18.4R3-S1, 19.1R2-S1, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2, 19.4R2-S1, 20.1R1, and all subsequent releases.
Standard security best common practices such as limiting packet toward the RE only from trusted networks/host using firewall filter in combination with source address anti-spoofing should be applied to reduce the risk of exposure.
| Product | Vulnerable range | Fixed version | Advisory |
|---|---|---|---|
| Juniper Networks Junos OS | >=18.4<18.4R2-S4, 18.4R3-S1 | 18.4R2-S4, 18.4R3-S1 | advisory ↗ |
| Juniper Networks Junos OS | >=19.1<19.1R2-S1, 19.1R3 | 19.1R2-S1, 19.1R3 | advisory ↗ |
| Juniper Networks Junos OS | >=19.2<19.2R1-S5, 19.2R2 | 19.2R1-S5, 19.2R2 | advisory ↗ |
| Juniper Networks Junos OS | >=19.3<19.3R2-S4, 19.3R3 | 19.3R2-S4, 19.3R3 | advisory ↗ |
| Juniper Networks Junos OS | >=19.4<19.4R1-S3, 19.4R2 | 19.4R1-S3, 19.4R2 | advisory ↗ |