An Improper Check for Unusual or Exceptional Conditions vulnerability in the packeIO daemon of Juniper Networks Junos OS Evolved on PTX10003, PTX10004, and PTX10008 allows an unauthenticated, network-based attacker to cause a Denial of Service (DoS). Continued receipt of these crafted packets will cause a sustained Denial of Service condition.
 

This issue affects Juniper Networks Junos OS Evolved all versions prior to 20.4R2-S3-EVO on PTX10003, PTX10004, and PTX10008.

This issue does not affect:

Juniper Networks Junos OS Evolved versions 21.1R1-EVO and above;

Juniper Networks Junos OS.
 

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
 

This issue was seen during production usage.
 

This issue has been assigned CVE-2022-22194.

The following software releases have been updated to resolve this specific issue: 20.4R2-S3-EVO, 20.4R3-EVO.
 

This issue is being tracked as PR 1614171 which is visible on the Customer Support website.
 

Note: Juniper SIRT's policy is not to evaluate releases which are beyond End of Engineering (EOE) or End of Life (EOL).
 

Implementation:

Software Releases, patches and updates are available at https://support.juniper.net/support/downloads/

One characteristic of this vulnerability is that an FPC restart will only be triggered by a crafted GRE packet which has its' TTL set to 0 or 1 so as a workaround a filter can be implemented that drops such packets:
 

set firewall family inet filter GREfilter term 1 from protocol gre
set firewall family inet filter GREfilter term 1 from ttl 0
set firewall family inet filter GREfilter term 1 then count gre-ttl-0
set firewall family inet filter GREfilter term 1 then discard
set firewall family inet filter GREfilter term 2 from protocol gre
set firewall family inet filter GREfilter term 2 from ttl 1
set firewall family inet filter GREfilter term 2 then count gre-ttl-1
set firewall family inet filter GREfilter term 2 then discard
set firewall family inet filter GREfilter term default then accept

An equivalent filter for family inet6 is required if IPv6 is configured on at least one interface.

• 2022-04-13: Initial Publication.

• KB16613: Overview of the Juniper Networks SIRT Quarterly Security Bulletin Publication Process [juniper.net]
• KB16765: In which releases are vulnerabilities fixed? [juniper.net]
• KB16446: Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories [juniper.net]
• Report a Security Vulnerability - How to Contact the Juniper Networks Security Incident Response Team
• CVE-2022-22194 at cve.mitre.org