CVE-2024-30389

Junos OS: EX4300 Series: Firewall filter not blocking egress traffic

Description

An Incorrect Behavior Order vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on EX4300 Series allows an unauthenticated, network-based attacker to cause an integrity impact to networks downstream of the vulnerable device. When an output firewall filter is applied to an interface it doesn't recognize matching packets but permits any traffic. This issue affects Junos OS 21.4 releases from 21.4R1 earlier than 21.4R3-S6. This issue does not affect Junos OS releases earlier than 21.4R1.

Remediation

Solution:

  • The following software release has been updated to resolve this specific issue: 21.4R3-S6, and all subsequent releases of this branch.

Workaround:

  • While there is no known workarounds for this issue, it is possible to recover by deactivating and then activating the filter. But please note that the issue might reoccur after a reboot or pfe restart.

Category

6.9
CVSS
Severity: Medium
CVSS 4.0 •
CVSS 3.1 •
EPSS 0.21%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
http://supportportal.juniper.net/JSA79185 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:N/VA:N/SC:N/SI:L/SA:N issue tracking technical description

Frequently Asked Questions

What is the severity of CVE-2024-30389?
CVE-2024-30389 has been scored as a medium severity vulnerability.
How to fix CVE-2024-30389?
To fix CVE-2024-30389: The following software release has been updated to resolve this specific issue: 21.4R3-S6, and all subsequent releases of this branch.
Is CVE-2024-30389 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-30389 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-2024-30389?
CVE-2024-30389 affects Juniper Networks Junos OS.
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