How severe is CVE-2021-28127?

CVE-2021-28127 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-28127 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-28127?

CVE-2021-28127 primarily affects Stormshield Stormshield Network Security. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-28127?

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-2021-28127 published?

CVE-2021-28127 was published on 2021-07-01 and last updated on 2026-06-17.

CVE-2021-28127

CVE-2021-28127 is a high-severity vulnerability in Stormshield Stormshield Network Security with a CVSS 3.x base score of 7.5. 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-307.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-307
Affected product: Stormshield Stormshield Network Security
Published: 2021-07-01
Last modified: 2026-06-17

Description

An issue was discovered in Stormshield SNS through 4.2.1. A brute-force attack can occur.

Frequently asked questions

What is CVE-2021-28127?: An issue was discovered in Stormshield SNS through 4.2.1. A brute-force attack can occur.
How severe is CVE-2021-28127?: CVE-2021-28127 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-28127 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-28127?: CVE-2021-28127 primarily affects Stormshield Stormshield Network Security. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-28127?: 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-2021-28127 published?: CVE-2021-28127 was published on 2021-07-01 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:stormshield:stormshield_network_security:*:*:*:*:*:*:*:*
cpe:2.3:a:stormshield:stormshield_network_security:4.2.1:*:*:*:*:*:*:*

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