CVE-2022-22217: An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an adj...

Description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an adjacent unauthenticated attacker to cause a Denial of Service (DoS). The issue is caused by malformed MLD packets looping on a multi-homed Ethernet Segment Identifier (ESI) when VXLAN is configured. These MLD packets received on a multi-homed ESI are sent to the peer, and then incorrectly forwarded out the same ESI, violating the split horizon rule. This issue only affects QFX10K Series switches, including the QFX10002, QFX10008, and QFX10016. Other products and platforms are unaffected by this vulnerability. This issue affects Juniper Networks Junos OS on QFX10K Series: All versions prior to 19.1R3-S9; 19.2 versions prior to 19.2R1-S9, 19.2R3-S5; 19.3 versions prior to 19.3R3-S6; 19.4 versions prior to 19.4R2-S7, 19.4R3-S8; 20.1 versions prior to 20.1R3-S4; 20.2 versions prior to 20.2R3-S4; 20.3 versions prior to 20.3R3-S2; 20.4 versions prior to 20.4R3-S2; 21.1 versions prior to 21.1R3; 21.2 versions prior to 21.2R2-S1, 21.2R3; 21.3 versions prior to 21.3R2.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.32%

24.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-754

Affected Software

Vendor	Product	Versions	Update
Juniper	Junos	< 19.1	—
Juniper	Junos	19.1	—
Juniper	Junos	19.2	—
Juniper	Junos	19.3	—
Juniper	Junos	19.4	—
Juniper	Junos	20.1	—
Juniper	Junos	20.2	—
Juniper	Junos	20.3	—
Juniper	Junos	20.4	—
Juniper	Junos	21.1	—
Juniper	Junos	21.2	—
Juniper	Junos	21.3	R1

References

https://kb.juniper.net/JSA69721Vendor Advisory
https://kb.juniper.net/JSA69721Vendor Advisory

Timeline

Published: Jul 20, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2022-22217?

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an adjacent unauthenticated attacker to cause a Denial of Service (DoS). The issue is caused by malformed MLD packets looping on a multi-homed Ethernet Segment Identifier (ESI) when VXLAN is configured. These MLD packets received on a multi-homed ESI are sent to the peer, and then incorrectly forwarded out the same ESI, violating the split horizon rule. This issue only affects QFX10K Series switches, including the QFX10002, QFX10008, and QFX10016. Other products and platforms are unaffected by this vulnerability. This issue affects Juniper Networks Junos OS on QFX10K Series: All versions prior to 19.1R3-S9; 19.2 versions prior to 19.2R1-S9, 19.2R3-S5; 19.3 versions prior to 19.3R3-S6; 19.4 versions prior to 19.4R2-S7, 19.4R3-S8; 20.1 versions prior to 20.1R3-S4; 20.2 versions prior to 20.2R3-S4; 20.3 versions prior to 20.3R3-S2; 20.4 versions prior to 20.4R3-S2; 21.1 versions prior to 21.1R3; 21.2 versions prior to 21.2R2-S1, 21.2R3; 21.3 versions prior to 21.3R2.

How severe is CVE-2022-22217?

CVE-2022-22217 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.32% probability of exploitation in the next 30 days.

How do I fix CVE-2022-22217?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.