Junos OS: SRX Series: High CPU load due to processing for HTTP traffic when Application Identification is enabled.

published 2020-10-16 6y ago modified 2026-06-17 4mo ago also EUVD-2020-12546

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 64%
public exploits: 0; none known

On Juniper Networks SRX Series configured with application identification inspection enabled, receipt of specific HTTP traffic can cause high CPU load utilization, which could lead to traffic interruption. Application identification is enabled by default and is automatically turned on when Intrusion Detection and Prevention (IDP), AppFW, AppQoS, or AppTrack is configured. Thus, this issue might occur when IDP, AppFW, AppQoS, or AppTrack is configured. This issue affects Juniper Networks Junos OS on SRX Series: 12.3X48 versions prior to 12.3X48-D105; 15.1X49 versions prior to 15.1X49-D221, 15.1X49-D230; 17.4 versions prior to 17.4R3-S3; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S3; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2; 18.4 versions prior to 18.4R2-S5, 18.4R3-S1; 19.1 versions prior to 19.1R2-S2, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R3; 19.4 versions prior to 19.4R2.

Patch / fix

fixed in 1

Juniper Networks Junos OS 12.3X48-D105, 15.1X49-D221, 15.1X49-D230, 17.4R3-S3, 18.1R3-S11, 18.2R3-S3, 18.3R2-S4, 18.3R3-S2, 18.4R2-S5, 18.4R3-S1, 19.1R2-S2, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R3, 19.4R2

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Exploit prediction

1.06% chance of exploitation in the next 30 days, higher than 64% 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	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	4.3	AV:N/AC:M/Au:N/C:N/I:N/A:P

Affected products

Juniper Networks Junos OS

Classification

Weakness

CWE-400 Uncontrolled Resource Consumption

References

kb.juniper.net /JSA11081
vendor-advisory

Sources

CVE List CVE-2020-1684
NVD CVE-2020-1684

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