How severe is CVE-2021-31384?

CVE-2021-31384 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-31384 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31384?

CVE-2021-31384 primarily affects Juniper Junos. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-31384?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-31384 published?

CVE-2021-31384 was published on 2021-10-19 and last updated on 2026-06-17.

CVE-2021-31384

CVE-2021-31384 is a high-severity vulnerability in Juniper Junos with a CVSS 3.x base score of 7.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-862.

Key facts

Severity: High (CVSS 3.x base score 7.2)
CVSS v2: 7.5
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-862
Affected product: Juniper Junos
Published: 2021-10-19
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2021-31384?: 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.
How severe is CVE-2021-31384?: CVE-2021-31384 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-31384 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31384?: CVE-2021-31384 primarily affects Juniper Junos. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-31384?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-31384 published?: CVE-2021-31384 was published on 2021-10-19 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:o:juniper:junos:20.4:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:20.4:r1-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:20.4:r2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.1:r1:*:*:*:*:*:*

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