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Fencer Intel
high 7.2

CVE-2021-31384 json

Junos OS: SRX Series: Under a specific device configuration an attacker can access the devices J-Web management services from any interface, regardless of security settings protecting the service

published 5y ago modified 4mo ago also EUVD-2021-18294

cvss
7.2
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.2%
EPSS 1.2% chance of exploitation in 30 days, percentile 67%
public exploits
0
none known

Summary

Due to a Missing Authorization weakness and Insufficient Granularity of Access Control in a specific device configuration, a vulnerability exists in Juniper Networks Junos OS on SRX Series whereby an attacker who attempts to access J-Web administrative interfaces can successfully do so from any device interface regardless of the web-management configuration and filter rules which may otherwise protect access to J-Web. This issue affects: Juniper Networks Junos OS SRX Series 20.4 version 20.4R1 and later versions prior to 20.4R2-S1, 20.4R3; 21.1 versions prior to 21.1R1-S1, 21.1R2. This issue does not affect Juniper Networks Junos OS versions prior to 20.4R1.

Patch / fix

  • Juniper Networks Junos OS 20.4R2-S1, 20.4R3, 21.1R1-S1, 21.1R2

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Exploit prediction

1.16% chance of exploitation in the next 30 days, higher than 67% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 7.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
NVD 3.1 10.0 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Affected products

  • Juniper Networks Junos OS

Classification

Weakness
  • CWE-285 Improper Authorization
  • CWE-862 Missing Authorization
  • CWE-551 Incorrect Behavior Order: Authorization Before Parsing and Canonicalization
  • CWE-939 Improper Authorization in Handler for Custom URL Scheme
  • CWE-1220 Insufficient Granularity of Access Control

References

Sources

Fencer Intel 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.