How severe is CVE-2021-41987?

CVE-2021-41987 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-41987 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 16% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41987?

CVE-2021-41987 primarily affects Mikrotik Routeros. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-41987?

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-2021-41987 published?

CVE-2021-41987 was published on 2022-03-16 and last updated on 2026-06-17.

CVE-2021-41987

CVE-2021-41987 is a high-severity vulnerability in Mikrotik Routeros with a CVSS 3.x base score of 8.1. Its EPSS exploit-prediction score of 16% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 16% (97th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Mikrotik Routeros
Published: 2022-03-16
Last modified: 2026-06-17

Description

In the SCEP Server of RouterOS in certain Mikrotik products, an attacker can trigger a heap-based buffer overflow that leads to remote code execution. The attacker must know the scep_server_name value. This affects RouterOS 6.46.8, 6.47.9, and 6.47.10.

Frequently asked questions

What is CVE-2021-41987?: In the SCEP Server of RouterOS in certain Mikrotik products, an attacker can trigger a heap-based buffer overflow that leads to remote code execution. The attacker must know the scep_server_name value. This affects RouterOS 6.46.8, 6.47.9, and 6.47.10.
How severe is CVE-2021-41987?: CVE-2021-41987 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-41987 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 16% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41987?: CVE-2021-41987 primarily affects Mikrotik Routeros. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-41987?: 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-2021-41987 published?: CVE-2021-41987 was published on 2022-03-16 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:o:mikrotik:routeros:6.46.8:*:*:*:*:*:*:*
cpe:2.3:o:mikrotik:routeros:6.47.9:*:*:*:*:*:*:*
cpe:2.3:o:mikrotik:routeros:6.47.10:*:*:*:*:*:*:*

More vulnerabilities in Mikrotik Routeros

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Threat intelligence

Threat-intel indicators referencing this CVE:

185.193.240.246 (ipv4-addr)