title: Junos OS and Junos OS Evolved: A BGP session will flap upon receipt of a specific, optional transitive attribute in version 22.3R1
description: An Improper Input Validation vulnerability in the Routing Protocol Daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated network-based attacker to cause a Denial of Service (DoS). If a BGP update message is received over an established BGP session, and that message contains a specific, optional transitive attribute, this session will be torn down with an update message error. This issue cannot propagate beyond an affected system as the processing error occurs as soon as the update is received. This issue is exploitable remotely as the respective attribute will propagate through unaffected systems and intermediate AS (if any). Continuous receipt of a BGP update containing this attribute will create a sustained Denial of Service (DoS) condition. Since this issue only affects 22.3R1, Juniper strongly encourages customers to move to 22.3R1-S1. Juniper SIRT felt that the need to promptly warn customers about this issue affecting the 22.3R1 versions of Junos OS and Junos OS Evolved warranted an Out of Cycle JSA. This issue affects: Juniper Networks Junos OS version 22.3R1. Juniper Networks Junos OS Evolved version 22.3R1-EVO. This issue does not affect: Juniper Networks Junos OS versions prior to 22.3R1. Juniper Networks Junos OS Evolved versions prior to 22.3R1-EVO.
problem types: CWE-20 Improper Input Validation
affected:
{
vendor: Juniper Networks
product: Junos OS
versions:
version: unspecified, lessThan: 22.3R1, status: unaffected, versionType: custom
version: 22.3, status: affected, lessThan: 22.3R1-S1, versionType: custom
}
{
vendor: Juniper Networks
product: Junos OS Evolved
versions:
version: unspecified, lessThan: 22.3R1-EVO, status: unaffected, versionType: custom
version: 22.3-EVO, status: affected, lessThan: 22.3R1-S1-EVO, versionType: custom
}
metrics:
cvssV3_1: [
version: 3.1
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
attackVector: NETWORK
attackComplexity: LOW
privilegesRequired: NONE
userInteraction: NONE
scope: UNCHANGED
confidentialityImpact: NONE
integrityImpact: NONE
availabilityImpact: HIGH
baseScore: 7.5
baseSeverity: HIGH
]
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: 22.3R1-S1, 22.3R2, 22.4R1, and all subsequent releases;
Junos OS Evolved: 22.3R1-S1-EVO, 22.3R2-EVO, 22.4R1-EVO, and all subsequent releases.
workarounds: There are no known workarounds for this issue.