How severe is CVE-2021-27180?

CVE-2021-27180 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-27180 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27180?

CVE-2021-27180 affects Altn Mdaemon. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27180?

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

When was CVE-2021-27180 published?

CVE-2021-27180 was published on 2021-04-14 and last updated on 2026-06-17.

CVE-2021-27180

CVE-2021-27180 is a medium-severity vulnerability in Altn Mdaemon with a CVSS 3.x base score of 6.1. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Altn Mdaemon
Published: 2021-04-14
Last modified: 2026-06-17

Description

An issue was discovered in MDaemon before 20.0.4. There is Reflected XSS in Webmail (aka WorldClient). It can be exploited via a GET request. It allows performing any action with the privileges of the attacked user.

Frequently asked questions

What is CVE-2021-27180?: An issue was discovered in MDaemon before 20.0.4. There is Reflected XSS in Webmail (aka WorldClient). It can be exploited via a GET request. It allows performing any action with the privileges of the attacked user.
How severe is CVE-2021-27180?: CVE-2021-27180 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-27180 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27180?: CVE-2021-27180 affects Altn Mdaemon. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27180?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-27180 published?: CVE-2021-27180 was published on 2021-04-14 and last updated on 2026-06-17.

References

Affected products (1)

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

More vulnerabilities in Altn Mdaemon

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CVE-2021-27181 — High (CVSS 8.8): An issue was discovered in MDaemon before 20.0.4. Remote Administration allows an attacker to perform a fixation of the…
CVE-2021-27183 — High (CVSS 7.2): An issue was discovered in MDaemon before 20.0.4. Administrators can use Remote Administration to exploit an Arbitrary…
CVE-2008-1358 — Medium (CVSS 6.5): Stack-based buffer overflow in the IMAP server in Alt-N Technologies MDaemon 9.6.4 allows remote authenticated users to…
CVE-2019-8984 — Medium (CVSS 6.1): MDaemon Webmail 14.x through 18.x before 18.5.2 has XSS (issue 2 of 2).
CVE-2019-8983 — Medium (CVSS 6.1): MDaemon Webmail 14.x through 18.x before 18.5.2 has XSS (issue 1 of 2).

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