How severe is CVE-2021-27183?

CVE-2021-27183 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-27183 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27183?

CVE-2021-27183 affects Altn Mdaemon. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27183?

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-2021-27183 published?

CVE-2021-27183 was published on 2021-04-14 and last updated on 2026-06-17.

CVE-2021-27183

CVE-2021-27183 is a high-severity vulnerability in Altn Mdaemon with a CVSS 3.x base score of 7.2. 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-610.

Key facts

Severity: High (CVSS 3.x base score 7.2)
CVSS v2: 6.5
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-610
Affected product: Altn Mdaemon
Published: 2021-04-14
Last modified: 2026-06-17

Description

An issue was discovered in MDaemon before 20.0.4. Administrators can use Remote Administration to exploit an Arbitrary File Write vulnerability. An attacker is able to create new files in any location of the filesystem, or he may be able to modify existing files. This vulnerability may directly lead to Remote Code Execution.

Frequently asked questions

What is CVE-2021-27183?: An issue was discovered in MDaemon before 20.0.4. Administrators can use Remote Administration to exploit an Arbitrary File Write vulnerability. An attacker is able to create new files in any location of the filesystem, or he may be able to modify existing files. This vulnerability may directly lead to Remote Code Execution.
How severe is CVE-2021-27183?: CVE-2021-27183 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-27183 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27183?: CVE-2021-27183 affects Altn Mdaemon. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27183?: 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-2021-27183 published?: CVE-2021-27183 was published on 2021-04-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:altn:mdaemon:*:*:*:*:*:*:*:*

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