CVE-2020-21387

mediumpriority · track · 24EPSS 0.006 · 47 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.57% (47th) EPSS

CVSS 4.3 · medium

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

A cross-site scripting (XSS) vulnerability in the parameter type_en of Maccms 10 allows attackers to obtain the administrator cookie and escalate privileges via a crafted payload.

cvss

Technical severity, 0–10. One row per scoring source.

6.1

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.7

v3.15.6mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimary

affected products (2)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
maccms maccms= 10.0nvdUScpe:2.3:a:maccms:maccms:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-10-04modified 2026-06-17

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An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0 and 10.0 and 10.1. A Cross-Site Scripting (XSS) vulnerability in the Zimbra Classic UI allows attackers to exec…
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+53007 more

references (5)

External citations — patches, advisories, analysis.

https://github.com/magicblack/maccms10Patchcnnvd
https://github.com/magicblack/maccms10/issues/126 cnnvd
https://nvd.nist.gov/vuln/detail/CVE-2020-21387 cnnvd
https://github.com/magicblack/maccms10/issues/126 enisa_euvd
https://github.com/magicblack/maccms10/issues/126ExploitIssue TrackingThird Party Advisorynvd

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