CVE-2024-30410

Junos OS: EX4300 Series: Loopback filter not blocking traffic despite having discard term.

MEDIUM

5.8

CVSS Score

Published: April 12, 2024 at 03:02 PM UTC

Updated: June 17, 2026 at 07:26 AM UTC

18 products affected across 2 vendorsJunosEx4300Ex4300-48T-Dc-Afi

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Severity

MEDIUM5.8

Exploit prediction

EPSS 0.4%

SSVC

No known exploit

Description

An Incorrect Behavior Order in the routing engine (RE) of Juniper Networks Junos OS on EX4300 Series allows traffic intended to the device to reach the RE instead of being discarded when the discard term is set in loopback (lo0) interface. The intended function is that the lo0 firewall filter takes precedence over the revenue interface firewall filter. This issue affects only IPv6 firewall filter. This issue only affects the EX4300 switch. No other products or platforms are affected by this vulnerability. This issue affects Juniper Networks Junos OS: * All versions before 20.4R3-S10, * from 21.2 before 21.2R3-S7, * from 21.4 before 21.4R3-S6.

Affected

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

Junos · Juniper Networks

95%

v < 20.4v < 20.4R3-S1021.2 ≤ v < 21.2R3-S721.4 ≤ v < 21.4r3-s620.4 20.4 r1 20.4 r1-s1 20.4 r2 20.4 r2-s1 20.4 r2-s2 20.4 r3 20.4 r3-s1 20.4 r3-s2 20.4 r3-s3 20.4 r3-s4 20.4 r3-s5 20.4 r3-s6 20.4 r3-s7 20.4 r3-s8 20.4 r3-s9 21.2 21.2 r1 21.2 r1-s1 21.2 r1-s2 21.2 r2 21.2 r2-s1 21.2 r2-s2 21.2 r3 21.2 r3-s1 21.2 r3-s2 21.2 r3-s3 21.2 r3-s4 21.2 r3-s5 21.2 r3-s6 21.4 21.4 r1 21.4 r1-s1 21.4 r1-s2 21.4 r2 21.4 r2-s1 21.4 r2-s2 21.4 r3 21.4 r3-s1 21.4 r3-s2 21.4 r3-s3 21.4 r3-s4 21.4 r3-s5

Affected range stops below 20.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.4R3-S10, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.2R3-S7, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.4R3-S6, so it looks safe — our inference, not a vendor statement

juniper-ex4300 (environment) · juniper-ex4300-24p (environment) · juniper-ex4300-24p-s (environment) · juniper-ex4300-24t (environment) · juniper-ex4300-24t-s (environment) · juniper-ex4300-32f (environment) · juniper-ex4300-32f-dc (environment) · juniper-ex4300-32f-s (environment) · juniper-ex4300-48mp (environment) · juniper-ex4300-48mp-s (environment) · juniper-ex4300-48p (environment) · juniper-ex4300-48p-s (environment) · juniper-ex4300-48t (environment) · juniper-ex4300-48t-afi (environment) · juniper-ex4300-48t-dc (environment) · juniper-ex4300-48t-dc-afi (environment) · juniper-ex4300-48t-s (environment)

Ex4300 · Juniperdevice

80%

All versions

Ex4300-24P · Juniperdevice

80%

All versions

Ex4300-24P-S · Juniperdevice

80%

All versions

Ex4300-24T · Juniperdevice

80%

All versions