CVE-2024-21607

Junos OS: MX Series and EX9200 Series: If the "tcp-reset" option used in an IPv6 filter, matched packets are accepted instead of rejected

Description

An Unsupported Feature in the UI vulnerability in Juniper Networks Junos OS on MX Series and EX9200 Series allows an unauthenticated, network-based attacker to cause partial impact to the integrity of the device. If the "tcp-reset" option is added to the "reject" action in an IPv6 filter which matches on "payload-protocol", packets are permitted instead of rejected. This happens because the payload-protocol match criteria is not supported in the kernel filter causing it to accept all packets without taking any other action. As a fix the payload-protocol match will be treated the same as a "next-header" match to avoid this filter bypass. This issue doesn't affect IPv4 firewall filters. This issue affects Juniper Networks Junos OS on MX Series and EX9200 Series: * All versions earlier than 20.4R3-S7; * 21.1 versions earlier than 21.1R3-S5; * 21.2 versions earlier than 21.2R3-S5; * 21.3 versions earlier than 21.3R3-S4; * 21.4 versions earlier than 21.4R3-S4; * 22.1 versions earlier than 22.1R3-S2; * 22.2 versions earlier than 22.2R3-S2; * 22.3 versions earlier than 22.3R2-S2, 22.3R3; * 22.4 versions earlier than 22.4R1-S2, 22.4R2-S2, 22.4R3.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S7, 21.1R3-S5, 21.2R3-S5, 21.3R3-S4, 21.4R3-S4, 22.1R3-S2, 22.2R3-S2, 22.3R2-S2, 22.3R3, 22.4R1-S2, 22.4R2-S2, 22.4R3, 23.2R1, and all subsequent releases.

Workaround:

  • A workarounds is to replace the payload-protocol match with a next-header match like in the following example: [ firewall family inet6 filter term match next-header] [ firewall family inet6 filter term then reject tcp-reset ]

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

Frequently Asked Questions

What is the severity of CVE-2024-21607?
CVE-2024-21607 has been scored as a medium severity vulnerability.
How to fix CVE-2024-21607?
To fix CVE-2024-21607: The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S7, 21.1R3-S5, 21.2R3-S5, 21.3R3-S4, 21.4R3-S4, 22.1R3-S2, 22.2R3-S2, 22.3R2-S2, 22.3R3, 22.4R1-S2, 22.4R2-S2, 22.4R3, 23.2R1, and all subsequent releases.
Is CVE-2024-21607 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-21607 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-2024-21607?
CVE-2024-21607 affects Juniper Networks Junos OS.
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