CVE-2021-0246

Junos OS: SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3: In a multi-tenant environment, a tenant host administrator may be able to jailbreak out of their network impacting other tenant networks or gather information from other networks.

HIGH

7.3

CVSS Score

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

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

8 products affected across 2 vendorsJunosSRX5600SRX5800

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Severity

HIGH7.3

Exploit prediction

EPSS 0.2%

Description

On SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3, devices using tenant services on Juniper Networks Junos OS, due to incorrect default permissions assigned to tenant system administrators a tenant system administrator may inadvertently send their network traffic to one or more tenants while concurrently modifying the overall device system traffic management, affecting all tenants and the service provider. Further, a tenant may inadvertently receive traffic from another tenant. This issue affects: Juniper Networks Junos OS 18.3 version 18.3R1 and later versions on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2; 18.3 versions prior to 18.3R3 on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2; 18.4 versions prior to 18.4R2 on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3; 19.1 versions prior to 19.1R2 on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3. This issue does not affect: Juniper Networks Junos OS versions prior to 18.3R1.

Affected

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

Junos · Juniper Networks

95%

18.3R1 ≤ v < 18.3*18.4 ≤ v < 18.4R219.1 ≤ v < 19.1R218.3 18.3 r1 18.3 r1-s1 18.3 r1-s2 18.3 r1-s3 18.3 r1-s4 18.3 r1-s5 18.3 r1-s6 18.3 r2 18.3 r2-s1 18.3 r2-s2 18.3 r2-s3 18.3 r2-s4 18.3R1 18.4 18.4 r1 18.4 r1-s1 18.4 r1-s2 18.4 r1-s3 18.4 r1-s4 18.4 r1-s5 18.4 r1-s6 18.4 r1-s7 19.1 19.1 r1 19.1 r1-s1 19.1 r1-s2 19.1 r1-s3 19.1 r1-s4 19.1 r1-s5

Affected range stops below 18.3*, so it looks safe — our inference, not a vendor statement

Vendor states this is fixed in 18.3R1 (unaffected)

Affected range stops below 18.4R2, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.1R2, so it looks safe — our inference, not a vendor statement

juniper-srx1500 (environment) · juniper-srx4100 (environment) · juniper-srx4200 (environment) · juniper-srx4600 (environment) · juniper-srx5400 (environment) · juniper-srx5600 (environment) · juniper-srx5800 (environment)

Srx1500 · Juniperdevice

80%

All versions

Srx4100 · Juniperdevice

80%

All versions

Srx4200 · Juniperdevice

80%

All versions

Srx4600 · Juniperdevice

80%

All versions