How severe is CVE-2021-4105?

CVE-2021-4105 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-4105 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4105?

CVE-2021-4105 primarily affects Bg-tek Coslat Bx5s1d3 Firmware. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-4105?

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

When was CVE-2021-4105 published?

CVE-2021-4105 was published on 2023-02-24 and last updated on 2026-06-17.

CVE-2021-4105

CVE-2021-4105 is a critical-severity vulnerability in Bg-tek Coslat Bx5s1d3 Firmware with a CVSS 3.x base score of 9.8. 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-755.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-755
Affected product: Bg-tek Coslat Bx5s1d3 Firmware
Published: 2023-02-24
Last modified: 2026-06-17

Description

Improper Handling of Parameters vulnerability in BG-TEK COSLAT Firewall allows Remote Code Inclusion. This issue affects COSLAT Firewall: from 5.24.0.R.20180630 before 5.24.0.R.20210727.

Frequently asked questions

What is CVE-2021-4105?: Improper Handling of Parameters vulnerability in BG-TEK COSLAT Firewall allows Remote Code Inclusion. This issue affects COSLAT Firewall: from 5.24.0.R.20180630 before 5.24.0.R.20210727.
How severe is CVE-2021-4105?: CVE-2021-4105 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-4105 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4105?: CVE-2021-4105 primarily affects Bg-tek Coslat Bx5s1d3 Firmware. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-4105?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-4105 published?: CVE-2021-4105 was published on 2023-02-24 and last updated on 2026-06-17.

References

Affected products (8)

cpe:2.3:o:bg-tek:coslat_bx5s1d3_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:bg-tek:coslat_bx5s1d4_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:bg-tek:coslat_bx5s1d5_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:bg-tek:coslat_rm1ds1000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:bg-tek:coslat_rm2ds2000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:bg-tek:coslat_rm2s200_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:bg-tek:coslat_rm3s300_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:bg-tek:coslat_rm4s500_firmware:*:*:*:*:*:*:*:*

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