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

MEDIUM
5.3
CVSS Score
Published: January 12, 2024 at 12:55 AM UTC
Updated: June 17, 2026 at 07:09 AM UTC
23 products affected across 2 vendorsJunosMx960Mx480

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Affected range stops below 20.4, so it looks safe — our inference, not a vendor statement
Affected range stops below 20.4R3-S7, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.1R3-S5, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.2R3-S5, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.3R3-S4, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.4R3-S4, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.1R3-S2, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.2R3-S2, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.3R2-S2, 22.3R3, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.4R1-S2, 22.4R2-S2, 22.4R3, so it looks safe — our inference, not a vendor statement
juniper-ex9200 (environment) · juniper-ex9204 (environment) · juniper-ex9208 (environment) · juniper-mx10 (environment) · juniper-mx10000 (environment) · juniper-mx10003 (environment) · juniper-mx10004 (environment) · juniper-mx10008 (environment) · juniper-mx10016 (environment) · juniper-mx104 (environment) · juniper-mx150 (environment) · juniper-mx2008 (environment) · juniper-mx2010 (environment) · juniper-mx2020 (environment) · juniper-mx204 (environment) · juniper-mx240 (environment) · juniper-mx304 (environment) · juniper-mx40 (environment) · juniper-mx480 (environment) · juniper-mx5 (environment) · juniper-mx80 (environment) · juniper-mx960 (environment)
All versions
All versions
All versions
All versions
All versions
All versions
All versions
All versions
All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUMjuniper
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-447NVD-CWE-Other

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