CVE-2021-0235: Junos OS: SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3, vSRX Series: In a multi-tenant environment, a tenant host administrator may configure logical firewall isolation affecting other tenant networks

Severity: medium (CVSS 4.6 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-04-22 · updated 2026-06-17
Weakness: CWE-276

Description

On SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3, vSRX Series devices using tenant services on Juniper Networks Junos OS, due to incorrect permission scheme 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; 18.4 version 18.4R1 and later versions on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3; 19.1 versions 19.1R1 and later versions on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3; 19.2 versions prior to 19.2R1-S6, 19.2R3-S2 on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3; 19.3 versions prior to 19.3R3-S2 on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3; 19.4 versions prior to 19.4R2-S4, 19.4R3-S2 on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3; 20.1 versions prior to 20.1R2, 20.1R3 on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3 vSRX Series; 20.2 versions prior to 20.2R2-S1, 20.2R3 on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3 vSRX Series; 20.3 versions prior to 20.3R1-S2, 20.3R2 on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3 vSRX Series; 20.4 versions prior to 20.4R1, 20.4R2 on SRX1500, SRX4100, SRX4200, SRX4600, SRX5000 Series with SPC2/SPC3 vSRX Series. This issue does not affect Juniper Networks Junos OS versions prior to 18.3R1.

Affected products

Juniper Junos OS: 18.3-r1, 18.3-r1-s1, 18.3-r1-s2, 18.3-r1-s3, 18.3-r1-s4, 18.3-r1-s5 (+85)

References

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