What is CVE-2020-1664?

CVE-2020-1664 is a high-severity vulnerability in Juniper Junos, classified under Stack-based Buffer Overflow. CVSS score: 7.8/10. Published 2020-10-16.

How severe is CVE-2020-1664?

High severity. CVSS v3 base score is 7.8 out of 10.

Is CVE-2020-1664 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Juniper Junos

CVE-2020-1664

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.

Vulnerability class: Buffer Overflow

Published 2020-10-16 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (34.4th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 34.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Juniper Junos — versions 17.3, 17.4, 18.1
Juniper Networks Junos OS — versions 17.3, 17.4, 18.1

Weakness classification (CWE)

Public proof-of-concept exploits

r0eXpeR/supplier

References

kb.juniper.net/JSA11061 (Vendor Advisory)

Frequently asked questions

What is CVE-2020-1664?: CVE-2020-1664 is a high-severity vulnerability in Juniper Junos, classified under Stack-based Buffer Overflow. CVSS score: 7.8/10. Published 2020-10-16.
How severe is CVE-2020-1664?: High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2020-1664 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.