Junos OS: EX4300/EX4600/QFX3500/QFX5100 Series: Stateless IP firewall filter may fail to evaluate certain packets

published 2020-01-15 6y ago modified 2026-06-17 4mo ago also EUVD-2020-12474

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.8%; EPSS 0.8% chance of exploitation in 30 days, percentile 58%
public exploits: 0; none known

On EX4300, EX4600, QFX3500, and QFX5100 Series, a vulnerability in the IP firewall filter component may cause the firewall filter evaluation of certain packets to fail. This issue only affects firewall filter evaluation of certain packets destined to the device Routing Engine (RE). This issue does not affect the Layer 2 firewall filter evaluation nor does it affect the Layer 3 firewall filter evaluation destined to connected hosts. This issue may occur when evaluating both IPv4 or IPv6 packets. This issue affects Juniper Networks Junos OS: 14.1X53 versions prior to 14.1X53-D12 on QFX5100 Series and EX4600 Series; 14.1X53 versions prior to 14.1X53-D52 on QFX3500 Series; 14.1X53 versions prior to 14.1X53-D48 on EX4300 Series; 15.1 versions prior to 15.1R7-S3 on EX4300 Series; 16.1 versions prior to 16.1R7 on EX4300 Series; 17.1 versions prior to 17.1R3 on EX4300 Series; 17.2 versions prior to 17.2R3 on EX4300 Series; 17.3 versions prior to 17.3R2-S5, 17.3R3 on EX4300 Series; 17.4 versions prior to 17.4R2 on EX4300 Series; 18.1 versions prior to 18.1R3 on EX4300 Series; 18.2 versions prior to 18.2R2 on EX4300 Series.

Patch / fix

fixed in 1

Juniper Networks Junos OS 14.1X53-D12, 14.1X53-D48, 14.1X53-D52, 15.1R7-S3, 16.1R7, 17.1R3, 17.2R3, 17.3R2-S5, 17.3R3, 17.4R2, 18.1R3, 18.2R2

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Exploit prediction

0.85% chance of exploitation in the next 30 days, higher than 58% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
NVD	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:P/A:N

Affected products

Juniper Networks Junos OS

Classification

Weakness

CWE-284 Improper Access Control

References

kb.juniper.net /JSA10983
vendor-advisory

Sources

CVE List CVE-2020-1604
NVD CVE-2020-1604

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