Junos OS: Buffer overflow vulnerability in device control daemon

published 2020-10-16 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-12526

cvss: 7.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 37%
public exploits: 0; none known

A stack buffer overflow vulnerability in the device control daemon (DCD) on Juniper Networks Junos OS allows a low privilege local user to create a Denial of Service (DoS) against the daemon or execute arbitrary code in the system with root privilege. This issue affects Juniper Networks Junos OS: 17.3 versions prior to 17.3R3-S9; 17.4 versions prior to 17.4R2-S12, 17.4R3-S3; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S6; 18.2X75 versions prior to 18.2X75-D53, 18.2X75-D65; 18.3 versions prior to 18.3R2-S4, 18.3R3-S4; 18.4 versions prior to 18.4R2-S5, 18.4R3-S5; 19.1 versions prior to 19.1R3-S3; 19.2 versions prior to 19.2R1-S5, 19.2R3; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2-S2, 19.4R3; 20.1 versions prior to 20.1R1-S4, 20.1R2; 20.2 versions prior to 20.2R1-S1, 20.2R2. Versions of Junos OS prior to 17.3 are unaffected by this vulnerability.

Patch / fix

fixed in 1

Juniper Networks Junos OS 17.3R3-S9, 17.4R2-S12, 17.4R3-S3, 18.1R3-S11, 18.2R3-S6, 18.2X75-D53, 18.2X75-D65, 18.3R2-S4, 18.3R3-S4, 18.4R2-S5, 18.4R3-S5, 19.1R3-S3, 19.2R1-S5, 19.2R3, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2-S2, 19.4R3, 20.1R1-S4, 20.1R2, 20.2R1-S1, 20.2R2

Exploit prediction

0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.2	AV:L/AC:L/Au:N/C:C/I:C/A:C

Affected products

Juniper Networks Junos OS

Classification

Weakness

CWE-121 Stack-based Buffer Overflow
CWE-787 Out-of-bounds Write

References

kb.juniper.net /JSA11061
vendor-advisory

Sources

CVE List CVE-2020-1664
NVD CVE-2020-1664

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Summary