CVE-2021-0266

cSRX: Use of Hard-coded Cryptographic Keys allows an attacker to take control of the device through device management services.

CRITICAL

9.8

CVSS Score

Published: April 22, 2021 at 07:37 PM UTC

Updated: June 17, 2026 at 03:29 AM UTC

2 products affected across 2 vendorsJunosCsrx

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Severity

CRITICAL9.8

Exploit prediction

EPSS 0.9%

Description

The use of multiple hard-coded cryptographic keys in cSRX Series software in Juniper Networks Junos OS allows an attacker to take control of any instance of a cSRX deployment through device management services. This issue affects: Juniper Networks Junos OS on cSRX Series: All versions prior to 20.2R3; 20.3 versions prior to 20.3R2; 20.4 versions prior to 20.4R2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Junos · Juniper Networks

95%

v < 20.2R320.3 ≤ v < 20.3R220.4 ≤ v < 20.4R220.2 r1 20.2 r1-s1 20.2 r1-s2 20.2 r1-s3 20.3 20.3 r1 20.3 r1-s1 20.4 20.4 r1 20.4 r1-s1

Affected range stops below 20.2R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.3R2, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.4R2, so it looks safe — our inference, not a vendor statement

juniper-csrx (environment)

Csrx · Juniperdevice

80%

All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://kb.juniper.net/JSA11157

References (1)

x_refsource_MISCVendor Advisory

Source: [email protected]

https://kb.juniper.net/JSA11157

CVSS

9.8CRITICAL[email protected]

Attack Vector: NETWORK
Complexity: LOW
Privileges: NONE
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: HIGH
Integrity: HIGH
Availability: HIGH

Vector?

Quick Info

StatusMODIFIED

CWE

CWE-321CWE-798

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