title: Junos OS: SRX 4600 and SRX 5000 Series: The receipt of specific genuine packets by SRXes configured for L2 transparency will cause a DoS
description: An Incomplete Internal State Distinction vulnerability in the packet forwarding engine (PFE) of Juniper Networks Junos OS on SRX 4600 and SRX 5000 Series allows an adjacent attacker to cause a Denial of Service (DoS).
If an SRX is configured in L2 transparent mode the receipt of a specific genuine packet can cause a single Packet Processing Engines (PPE) component of the PFE to run into a loop, which in turn will render the PPE unavailable. Each packet will cause one PPE to get into a loop, leading to a gradual performance degradation until all PPEs are unavailable and all traffic processing stops. To recover the affected FPC need to be restarted.
This issue affects Juniper Networks Junos OS on SRX 4600 and SRX 5000 Series:
20.1 version 20.1R1 and later versions;
20.2 versions prior to 20.2R3-S7;
20.3 version 20.3R1 and later versions;
20.4 versions prior to 20.4R3-S7;
21.1 versions prior to 21.1R3-S5;
21.2 versions prior to 21.2R3-S3;
21.3 versions prior to 21.3R3-S3;
21.4 versions prior to 21.4R3-S1;
22.1 versions prior to 22.1R3;
22.2 versions prior to 22.2R2;
22.3 versions prior to 22.3R1-S1, 22.3R2.
problem types: CWE-372 Incomplete Internal State Distinction
affected:
{
defaultStatus: unaffected
platforms: [SRX4600, SRX 5000 Series]
product: Junos OS
vendor: Juniper Networks
versions:
changes: [at: 20.1R1, status: affected], lessThan: 20.1*, status: affected, version: 20.1, versionType: custom
lessThan: 20.2R3-S7, status: affected, version: 20.2, versionType: custom
changes: [at: 20.3R1, status: affected], lessThan: 20.3*, status: affected, version: 20.3, versionType: custom
lessThan: 20.4R3-S7, status: affected, version: 20.4, versionType: custom
lessThan: 21.1R3-S5, status: affected, version: 21.1, versionType: custom
lessThan: 21.2R3-S3, status: affected, version: 21.2, versionType: custom
lessThan: 21.3R3-S3, status: affected, version: 21.3, versionType: custom
lessThan: 21.4R3-S1, status: affected, version: 21.4, versionType: custom
lessThan: 22.1R3, status: affected, version: 22.1, versionType: custom
lessThan: 22.2R2, status: affected, version: 22.2, versionType: custom
lessThan: 22.3R1-S1, 22.3R2, status: affected, version: 22.3, versionType: custom
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: ADJACENT_NETWORK
availabilityImpact: HIGH
baseScore: 6.5
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
version: 3.1
]
format: CVSS
scenarios: GENERAL
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 20.2R3-S7, 20.4R3-S7, 21.1R3-S5, 21.2R3-S3, 21.3R3-S3, 21.4R3-S1, 22.1R3, 22.2R2, 22.3R1-S1, 22.3R2, 22.4R1, and all subsequent releases.
workarounds: There are no known workarounds for this issue.