CVE-2024-21603

Junos OS: MX Series: Gathering statistics in a scaled SCU/DCU configuration will lead to a device crash

Description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the kernel of Juniper Network Junos OS on MX Series allows a network based attacker with low privileges to cause a denial of service. If a scaled configuration for Source class usage (SCU) / destination class usage (DCU) (more than 10 route classes) is present and the SCU/DCU statistics are gathered by executing specific SNMP requests or CLI commands, a 'vmcore' for the RE kernel will be seen which leads to a device restart. Continued exploitation of this issue will lead to a sustained DoS. This issue only affects MX Series devices with MPC10, MPC11 or LC9600, and MX304. No other MX Series devices are affected. This issue affects Juniper Networks Junos OS: * All versions earlier than 20.4R3-S9; * 21.2 versions earlier than 21.2R3-S6; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3; * 22.1 versions earlier than 22.1R3; * 22.2 versions earlier than 22.2R2; * 22.3 versions earlier than 22.3R2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S9, 21.2R3-S6, 21.3R3-S5, 21.4R3, 22.1R3, 22.2R2, 22.3R2, 22.4R1, and all subsequent releases.

Workaround:

  • There are no known workarounds for this issue.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.06%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2024-21603?
CVE-2024-21603 has been scored as a medium severity vulnerability.
How to fix CVE-2024-21603?
To fix CVE-2024-21603: The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S9, 21.2R3-S6, 21.3R3-S5, 21.4R3, 22.1R3, 22.2R2, 22.3R2, 22.4R1, and all subsequent releases.
Is CVE-2024-21603 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-21603 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2024-21603?
CVE-2024-21603 affects Juniper Networks Junos OS.
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