CVE-2023-28974: An Improper Check for Unusual or Exceptional Conditions vulnerability in the bbe-smgd of Juniper Networks Junos OS allows an unauthenticated, adjacent...

Description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the bbe-smgd of Juniper Networks Junos OS allows an unauthenticated, adjacent attacker to cause a Denial of Service (DoS). In a Broadband Edge / Subscriber Management scenario on MX Series when a specifically malformed ICMP packet addressed to the device is received from a subscriber the bbe-smgd will crash, affecting the subscriber sessions that are connecting, updating, or terminating. Continued receipt of such packets will lead to a sustained DoS condition. When this issue happens the below log can be seen if the traceoptions for the processes smg-service are enabled: BBE_TRACE(TRACE_LEVEL_INFO, "%s: Dropped unsupported ICMP PKT ... This issue affects Juniper Networks Junos OS on MX Series: All versions prior to 19.4R3-S11; 20.2 versions prior to 20.2R3-S7; 20.3 versions prior to 20.3R3-S6; 20.4 versions prior to 20.4R3-S6; 21.1 versions prior to 21.1R3-S4; 21.2 versions prior to 21.2R3-S4; 21.3 versions prior to 21.3R3-S3; 21.4 versions prior to 21.4R3-S2; 22.1 versions prior to 22.1R2-S2, 22.1R3; 22.2 versions prior to 22.2R2; 22.3 versions prior to 22.3R1-S2, 22.3R2.

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

0.30%

21.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-754

Affected Software

Vendor	Product	Versions	Update
Juniper	Junos	< 19.4	—
Juniper	Junos	19.4	—
Juniper	Junos	20.2	—
Juniper	Junos	20.3	—
Juniper	Junos	21.1	—
Juniper	Junos	21.2	—
Juniper	Junos	21.3	—
Juniper	Junos	21.4	—
Juniper	Junos	22.1	R1
Juniper	Junos	22.2	R1
Juniper	Junos	22.3	R1

References

https://supportportal.juniper.net/JSA70599Vendor Advisory
https://supportportal.juniper.net/JSA70599Vendor Advisory

Timeline

Published: Apr 17, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-28974?

An Improper Check for Unusual or Exceptional Conditions vulnerability in the bbe-smgd of Juniper Networks Junos OS allows an unauthenticated, adjacent attacker to cause a Denial of Service (DoS). In a Broadband Edge / Subscriber Management scenario on MX Series when a specifically malformed ICMP packet addressed to the device is received from a subscriber the bbe-smgd will crash, affecting the subscriber sessions that are connecting, updating, or terminating. Continued receipt of such packets will lead to a sustained DoS condition. When this issue happens the below log can be seen if the traceoptions for the processes smg-service are enabled: BBE_TRACE(TRACE_LEVEL_INFO, "%s: Dropped unsupported ICMP PKT ... This issue affects Juniper Networks Junos OS on MX Series: All versions prior to 19.4R3-S11; 20.2 versions prior to 20.2R3-S7; 20.3 versions prior to 20.3R3-S6; 20.4 versions prior to 20.4R3-S6; 21.1 versions prior to 21.1R3-S4; 21.2 versions prior to 21.2R3-S4; 21.3 versions prior to 21.3R3-S3; 21.4 versions prior to 21.4R3-S2; 22.1 versions prior to 22.1R2-S2, 22.1R3; 22.2 versions prior to 22.2R2; 22.3 versions prior to 22.3R1-S2, 22.3R2.

How severe is CVE-2023-28974?

CVE-2023-28974 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.30% probability of exploitation in the next 30 days.

How do I fix CVE-2023-28974?

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.