Junos OS: SRX Series: An attacker sending spoofed packets to IPSec peers may cause a Denial of Service.

published 2020-10-16 6y ago modified 2026-06-17 4mo ago also EUVD-2020-12522

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.3%; EPSS 1.3% chance of exploitation in 30 days, percentile 70%
public exploits: 0; none known

On SRX Series devices, a vulnerability in the key-management-daemon (kmd) daemon of Juniper Networks Junos OS allows an attacker to spoof packets targeted to IPSec peers before a security association (SA) is established thereby causing a failure to set up the IPSec channel. Sustained receipt of these spoofed packets can cause a sustained Denial of Service (DoS) condition. This issue affects IPv4 and IPv6 implementations. This issue affects Juniper Networks Junos OS on SRX Series: 12.3X48 versions prior to 12.3X48-D90; 15.1X49 versions prior to 15.1X49-D190; 17.4 versions prior to 17.4R2-S9, 17.4R3; 18.1 versions prior to 18.1R3-S9; 18.2 versions prior to 18.2R3; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S6, 18.4R2-S3, 18.4R3; 19.1 versions prior to 19.1R1-S4, 19.1R2. This issue does not affect 12.3 or 15.1 releases which are non-SRX Series releases.

Patch / fix

fixed in 1

Juniper Networks Junos OS 12.3X48-D90, 15.1X49-D190, 17.4R2-S9, 17.4R3, 18.1R3-S9, 18.2R3, 18.3R1-S7, 18.3R2-S3, 18.3R3, 18.4R1-S6, 18.4R2-S3, 18.4R3, 19.1R1-S4, 19.1R2

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Exploit prediction

1.29% chance of exploitation in the next 30 days, higher than 70% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

Juniper Networks Junos OS

Classification

Weakness

CWE-408 Incorrect Behavior Order: Early Amplification

References

kb.juniper.net /JSA11050
vendor-advisory

Sources

CVE List CVE-2020-1657
NVD CVE-2020-1657

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