How severe is CVE-2021-28665?

CVE-2021-28665 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 none, integrity none, and availability high.

Is CVE-2021-28665 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-28665?

CVE-2021-28665 primarily affects 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-2021-28665?

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-2021-28665 published?

CVE-2021-28665 was published on 2021-05-06 and last updated on 2026-06-17.

CVE-2021-28665

CVE-2021-28665 is a high-severity vulnerability in 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-401.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-401
Affected product: Stormshield Network Security
Published: 2021-05-06
Last modified: 2026-06-17

Description

Stormshield SNS with versions before 3.7.18, 3.11.6 and 4.1.6 has a memory-management defect in the SNMP plugin that can lead to excessive consumption of memory and CPU resources, and possibly a denial of service.

Frequently asked questions

What is CVE-2021-28665?: Stormshield SNS with versions before 3.7.18, 3.11.6 and 4.1.6 has a memory-management defect in the SNMP plugin that can lead to excessive consumption of memory and CPU resources, and possibly a denial of service.
How severe is CVE-2021-28665?: CVE-2021-28665 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 none, integrity none, and availability high.
Is CVE-2021-28665 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-28665?: CVE-2021-28665 primarily affects 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-2021-28665?: 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-2021-28665 published?: CVE-2021-28665 was published on 2021-05-06 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:stormshield:network_security:*:*:*:*:*:*:*:*
cpe:2.3:a:stormshield:stormshield_network_security:*:*:*:*:*:*:*:*

More vulnerabilities in Stormshield Network Security

CVE-2021-45885 — High (CVSS 7.5): An issue was discovered in Stormshield Network Security (SNS) 4.2.2 through 4.2.7 (fixed in 4.2.8). Under a specific…
CVE-2022-22703 — Medium (CVSS 5.5): In Stormshield SSO Agent 2.x before 2.1.1 and 3.x before 3.0.2, the cleartext user password and PSK are contained in…

All CVEs affecting Stormshield Network Security →

Other CWE-401 (Missing Release of Memory after Effective Lifetime) vulnerabilities

CVE-2026-46289 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: lib/scatterlist: fix length calculations in…
CVE-2022-0742 — Critical (CVSS 9.1): Memory leak in icmp6 implementation in Linux Kernel 5.13+ allows a remote attacker to DoS a host by making it go…
CVE-2024-25450 — High (CVSS 8.8): imlib2 v1.9.1 was discovered to mishandle memory allocation in the function init_imlib_fonts().
CVE-2023-33718 — High (CVSS 8.8): mp4v2 v2.1.3 was discovered to contain a memory leak via MP4File::ReadString() at mp4file_io.cpp
CVE-2021-40633 — High (CVSS 8.8): A memory leak (out-of-memory) in gif2rgb in util/gif2rgb.c in giflib 5.1.4 allows remote attackers trigger an out of…
CVE-2021-3492 — High (CVSS 8.8): Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring…

Browse all CWE-401 (Missing Release of Memory after Effective Lifetime) vulnerabilities →