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.

published 2021-04-22 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-2865

cvss: 7.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 14%
public exploits: 0; none known

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.

Patch / fix

fixed in 1

Juniper Networks Junos OS 18.3R3, 18.4R2, 19.1R2

Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.3	CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:L/I:H/A:L
NVD	2.0	4.6	AV:L/AC:L/Au:N/C:P/I:P/A:P

Affected products

Juniper Networks Junos OS

Classification

Weakness

CWE-276 Incorrect Default Permissions

References

kb.juniper.net /JSA11139
vendor-advisory

Sources

CVE List CVE-2021-0246
NVD CVE-2021-0246

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary