A denial of service vulnerability in telnetd service on Juniper Networks Junos OS allows remote unauthenticated attackers to cause a denial of service. Affected Junos OS releases are: 12.1X46 prior to 12.1X46-D71; 12.3X48 prior to 12.3X48-D50; 14.1 prior to 14.1R8-S5, 14.1R9; 14.1X53 prior to 14.1X53-D50; 14.2 prior to 14.2R7-S9, 14.2R8; 15.1 prior to 15.1F2-S16, 15.1F5-S7, 15.1F6-S6, 15.1R5-S2, 15.1R6; 15.1X49 prior to 15.1X49-D90; 15.1X53 prior to 15.1X53-D47; 16.1 prior to 16.1R4-S1, 16.1R5; 16.2 prior to 16.2R1-S3, 16.2R2;
The product does not properly control the allocation and maintenance of a limited resource.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Junos | Juniper | 12.1x45 (including) | 12.1x45 (including) |
| Junos | Juniper | 12.3x48 (including) | 12.3x48 (including) |
| Junos | Juniper | 14.1 (including) | 14.1 (including) |
| Junos | Juniper | 14.1x53 (including) | 14.1x53 (including) |
| Junos | Juniper | 14.2 (including) | 14.2 (including) |
| Junos | Juniper | 15.1 (including) | 15.1 (including) |
| Junos | Juniper | 15.1x49 (including) | 15.1x49 (including) |
| Junos | Juniper | 15.1x53 (including) | 15.1x53 (including) |
| Junos | Juniper | 16.1 (including) | 16.1 (including) |
| Junos | Juniper | 16.2 (including) | 16.2 (including) |
Mitigation of resource exhaustion attacks requires that the target system either:
The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.