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
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Junos OS: MX Series and EX9200 Series: If the "tcp-reset" option used in an IPv6 filter, matched packets are accepted instead of rejected
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.
- Record
CVE-2024-21607- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-447
- Updated
- 2026-11-02
EUVDEUVD-2024-19255
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.
- Record
EUVD-2024-19255- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-84c9-gp6c-qg45
An Unsupported Feature in the UI vulnerability in Juniper Networks Junos OS on MX Series and...
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.
- Record
GHSA-84c9-gp6c-qg45- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-447
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2024-21607- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-447
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2024-21607 is a medium vulnerability (CVSS 5.3) in Juniper Junos, published January 12, 2024. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.31%, the 23rd percentile. No source names a fixed version.