title: Junos OS and Junos OS Evolved: MX Series with MPC10/MPC11, PTX10003, PTX10008: Line card may crash and restart when traffic is hitting a firewall filter having a term with syslog action configured
description: A vulnerability in the processing of traffic matching a firewall filter containing a syslog action in Juniper Networks Junos OS on MX Series with MPC10/MPC11 cards installed, PTX10003 and PTX10008 Series devices, will cause the line card to crash and restart, creating a Denial of Service (DoS). Continued receipt and processing of packets matching the firewall filter can create a sustained Denial of Service (DoS) condition. When traffic hits the firewall filter, configured on lo0 or any physical interface on the line card, containing a term with a syslog action (e.g. 'term <name> then syslog'), the affected line card will crash and restart, impacting traffic processing through the ports of the line card. This issue only affects MX Series routers with MPC10 or MPC11 line cards, and PTX10003 or PTX10008 Series packet transport routers. No other platforms or models of line cards are affected by this issue. Note: This issue has also been identified and described in technical service bulletin TSB17931 (login required). This issue affects: Juniper Networks Junos OS on MX Series: 19.3 versions prior to 19.3R3-S2; 19.4 versions prior to 19.4R3-S2; 20.1 versions prior to 20.1R3; 20.2 versions prior to 20.2R2-S2, 20.2R3; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R2. Juniper Networks Junos OS Evolved on PTX10003, PTX10008: All versions prior to 20.4R2-EVO. This issue does not affect Juniper Networks Junos OS versions prior to 19.3R1.
problem types: CWE-703 Improper Check or Handling of Exceptional Conditions
affected:
{
product: Junos OS
vendor: Juniper Networks
versions:
lessThan: 19.3R1, status: unaffected, version: unspecified, versionType: custom
}
{
platforms: MX Series
product: Junos OS
vendor: Juniper Networks
versions:
lessThan: 19.3R3-S2, status: affected, version: 19.3, versionType: custom
lessThan: 19.4R3-S2, status: affected, version: 19.4, versionType: custom
lessThan: 20.1R3, status: affected, version: 20.1, versionType: custom
lessThan: 20.2R2-S2, 20.2R3, status: affected, version: 20.2, versionType: custom
lessThan: 20.3R3, status: affected, version: 20.3, versionType: custom
lessThan: 20.4R2, status: affected, version: 20.4, versionType: custom
}
{
platforms: PTX10003, PTX10008
product: Junos OS Evolved
vendor: Juniper Networks
versions:
lessThan: 20.4R2-EVO, status: affected, version: unspecified, versionType: custom
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: HIGH
baseScore: 5.9
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
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 19.4R3-S2, 20.1R3, 20.2R2-S2, 20.2R3, 20.3R3, 20.4R2, 21.1R1, and all subsequent releases.
Junos OS Evolved 20.4R2-EVO, 21.1R1-EVO, and all subsequent releases.
workarounds: Remove the "syslog" action from the firewall filter configuration.