title: Junos OS and Junos OS Evolved: After receiving a specific number of crafted packets snmpd will segmentation fault (SIGSEGV) requiring a manual restart.
description: A release of illegal memory vulnerability in the snmpd daemon of Juniper Networks Junos OS, Junos OS Evolved allows an attacker to halt the snmpd daemon causing a sustained Denial of Service (DoS) to the service until it is manually restarted. This issue impacts any version of SNMP – v1,v2, v3 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 18.4R2-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 19.4R2-S5, 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 21.1R2-S2, 21.1R3; 21.2 versions prior to 21.2R1-S2, 21.2R2. Juniper Networks Junos OS Evolved 21.2 versions prior to 21.2R3-EVO; 21.3 versions prior to 21.3R2-EVO.
problem types: Release of illegal memory
affected:
{
product: Junos OS
vendor: Juniper Networks
versions:
lessThan: 12.3R12-S20, status: affected, version: 12.3, versionType: custom
lessThan: 15.1R7-S11, status: affected, version: 15.1, versionType: custom
lessThan: 18.3R3-S6, status: affected, version: 18.3, versionType: custom
lessThan: 18.4R2-S9, 18.4R3-S10, status: affected, version: 18.4, versionType: custom
lessThan: 19.1R2-S3, 19.1R3-S7, status: affected, version: 19.1, versionType: custom
lessThan: 19.2R1-S8, 19.2R3-S4, status: affected, version: 19.2, versionType: custom
lessThan: 19.3R3-S4, status: affected, version: 19.3, versionType: custom
lessThan: 19.4R2-S5, 19.4R3-S6, status: affected, version: 19.4, versionType: custom
lessThan: 20.1R3-S2, status: affected, version: 20.1, versionType: custom
lessThan: 20.2R3-S3, status: affected, version: 20.2, versionType: custom
lessThan: 20.3R3-S1, status: affected, version: 20.3, versionType: custom
lessThan: 20.4R3, status: affected, version: 20.4, versionType: custom
lessThan: 21.1R2-S2, 21.1R3, status: affected, version: 21.1, versionType: custom
lessThan: 21.2R1-S2, 21.2R2, status: affected, version: 21.2, versionType: custom
}
{
product: Junos OS Evolved
vendor: Juniper Networks
versions:
lessThan: 21.2R3-EVO, status: affected, version: unspecified, versionType: custom
lessThan: 21.3R2-EVO, status: affected, version: 21.3, versionType: custom
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 5.3
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
version: 3.1
]
exploits: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
solutions: The following software releases have been updated to resolve this specific issue:
Junos OS: 12.3R12-S20, 15.1R7-S11, 18.3R3-S6, 18.4R2-S9, 18.4R3-S10, 19.1R2-S3, 19.1R3-S7, 19.2R1-S8, 19.2R3-S4, 19.3R3-S4, 19.4R2-S5, 19.4R3-S6, 20.1R3-S2, 20.2R3-S3, 20.3R3-S1, 20.4R3, 21.1R2-S2, 21.1R3, 21.2R1-S2, 21.2R2, 21.3R1, and all subsequ ent releases.
Junos OS Evolved: 21.2R3-EVO, 21.3R2-EVO, 21.4R1-EVO, and all subsequent releases.
workarounds: There are no workarounds for this issue.
For V1, V2 you can reduce the risk of exploitation by configuring the client-list to limit access to network management system (NMS) machines.
See the Network Management and Monitoring Guide for further instructions.
example:
[snmp client-list client-list-name "ip-addresses";]
For V3 you can reduce the risk of exploitation by configuring SNMP security to trusted devices only.
For any release of SNMP you can reduce the risk of exploitation by implementing source and destination IP filter rules as well as using Read Only communities where possible.
Regardless of these risk reduction methods, an attacker able to spoof trusted IP addresses can send the attack to an exposed and reachable SNMP RW community.