CVE-2024-21597

Junos OS: MX Series: In an AF scenario traffic can bypass configured lo0 firewall filters

Description

An Exposure of Resource to Wrong Sphere vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX Series allows an unauthenticated, network-based attacker to bypass the intended access restrictions. In an Abstracted Fabric (AF) scenario if routing-instances (RI) are configured, specific valid traffic destined to the device can bypass the configured lo0 firewall filters as it's received in the wrong RI context. This issue affects Juniper Networks Junos OS on MX Series: * All versions earlier than 20.4R3-S9; * 21.2 versions earlier than 21.2R3-S3; * 21.4 versions earlier than 21.4R3-S5; * 22.1 versions earlier than 22.1R3; * 22.2 versions earlier than 22.2R3; * 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-S3, 21.4R3-S5, 22.1R3, 22.2R3, 22.3R2, 22.4R1, and all subsequent releases.

Workaround:

  • There are no known workarounds for this issue.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.03%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://supportportal.juniper.net/JSA75738 vendor advisory
https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N technical description third party advisory

Frequently Asked Questions

What is the severity of CVE-2024-21597?
CVE-2024-21597 has been scored as a medium severity vulnerability.
How to fix CVE-2024-21597?
To fix CVE-2024-21597: The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S9, 21.2R3-S3, 21.4R3-S5, 22.1R3, 22.2R3, 22.3R2, 22.4R1, and all subsequent releases.
Is CVE-2024-21597 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-21597 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-2024-21597?
CVE-2024-21597 affects Juniper Networks Junos OS.
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