What’s Vulnerable › Vulnerabilities

CVE-2021-4105: Unauthenticated Remote Code Execution on COSLAT Firewall

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-02-24 · updated 2026-06-17
• Weakness: CWE-755

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.

Affected products

• BG-TEK Coslat Bx5S1D3 Firmware: from 5.24.0.r.20180630 before 5.24.0.r.20210727 — fixed in 5.24.0.r.20210727
• BG-TEK Coslat Bx5S1D4 Firmware: from 5.24.0.r.20180630 before 5.24.0.r.20210727 — fixed in 5.24.0.r.20210727
• BG-TEK Coslat Bx5S1D5 Firmware: from 5.24.0.r.20180630 before 5.24.0.r.20210727 — fixed in 5.24.0.r.20210727
• BG-TEK Coslat Rm1Ds1000 Firmware: from 5.24.0.r.20180630 before 5.24.0.r.20210727 — fixed in 5.24.0.r.20210727
• BG-TEK Coslat Rm2Ds2000 Firmware: from 5.24.0.r.20180630 before 5.24.0.r.20210727 — fixed in 5.24.0.r.20210727
• BG-TEK Coslat Rm2S200 Firmware: from 5.24.0.r.20180630 before 5.24.0.r.20210727 — fixed in 5.24.0.r.20210727
• BG-TEK Coslat Rm3S300 Firmware: from 5.24.0.r.20180630 before 5.24.0.r.20210727 — fixed in 5.24.0.r.20210727
• BG-TEK Coslat Rm4S500 Firmware: from 5.24.0.r.20180630 before 5.24.0.r.20210727 — fixed in 5.24.0.r.20210727

How to fix

Upgrade to a fixed version: BG-TEK Coslat Bx5S1D3 Firmware 5.24.0.r.20210727; BG-TEK Coslat Bx5S1D4 Firmware 5.24.0.r.20210727; BG-TEK Coslat Bx5S1D5 Firmware 5.24.0.r.20210727; BG-TEK Coslat Rm1Ds1000 Firmware 5.24.0.r.20210727; BG-TEK Coslat Rm2Ds2000 Firmware 5.24.0.r.20210727; BG-TEK Coslat Rm2S200 Firmware 5.24.0.r.20210727; BG-TEK Coslat Rm3S300 Firmware 5.24.0.r.20210727; BG-TEK Coslat Rm4S500 Firmware 5.24.0.r.20210727. Check the vendor advisory for mitigations.

References

• http://blog.coslat.com/2021/07/onemli-kritik-guncelleme-2021-07-27.html
• https://siberguvenlik.gov.tr/guvenlik-bildirimleri/detay/tr-23-0108
• https://www.usom.gov.tr/bildirim/tr-23-0108
• http://blog.coslat.com/2021/07/onemli-kritik-guncelleme-2021-07-27.html
• https://www.usom.gov.tr/bildirim/tr-23-0108

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