How severe is CVE-2020-20221?

CVE-2020-20221 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-20221 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-20221?

CVE-2020-20221 affects Mikrotik Routeros. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-20221?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-20221 published?

CVE-2020-20221 was published on 2021-07-21 and last updated on 2026-06-17.

CVE-2020-20221

CVE-2020-20221 is a medium-severity vulnerability in Mikrotik Routeros with a CVSS 3.x base score of 6.5. 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-400.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 6.8
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Mikrotik Routeros
Published: 2021-07-21
Last modified: 2026-06-17

Description

Mikrotik RouterOs before 6.44.6 (long-term tree) suffers from an uncontrolled resource consumption vulnerability in the /nova/bin/cerm process. An authenticated remote attacker can cause a Denial of Service due to overloading the systems CPU.

Frequently asked questions

What is CVE-2020-20221?: Mikrotik RouterOs before 6.44.6 (long-term tree) suffers from an uncontrolled resource consumption vulnerability in the /nova/bin/cerm process. An authenticated remote attacker can cause a Denial of Service due to overloading the systems CPU.
How severe is CVE-2020-20221?: CVE-2020-20221 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-20221 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-20221?: CVE-2020-20221 affects Mikrotik Routeros. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-20221?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-20221 published?: CVE-2020-20221 was published on 2021-07-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:mikrotik:routeros:*:*:*:*:ltr:*:*:*

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Browse all CWE-400 (Uncontrolled Resource Consumption) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

35.130.111.146 (ipv4-addr)
35.130.111.98 (ipv4-addr)
27.110.176.222 (ipv4-addr)