CVE-2021-27401

mediumpriority · track · 24EPSS 0.006 · 48 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.59% (48th) EPSS

CVSS 4.3 · medium

Is it mine?

3 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

The Join Meeting page of Mitel MiCollab Web Client before 9.2 FP2 could allow an attacker to access (view and modify) user data by executing arbitrary code due to insufficient input validation, aka Cross-Site Scripting (XSS).

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 (3)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
mitel micollab< 9.2nvdUScpe:2.3:a:mitel:micollab:*:*:*:*:*:*:*:*
mitel micollab= 9.2nvdUScpe:2.3:a:mitel:micollab:*:*:*:*:*:*:*:*

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 2021-08-13modified 2026-06-17

related (53,013)

Related entries.

ID	severity	EPSS	exploitable	published
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Roundcube Webmail before 1.5.12 and 1.6 before 1.6.12 is prone to a Cross-Site-Scripting (XSS) vulnerability via the animate tag in an SVG document.
CVE-2025-48700US	—OT critical	1.71% (77th)	KEV	2025-06-23
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…
CVE-2025-27915US	—OT critical	4.06% (91st)	KEV	2025-03-12
An issue was discovered in Zimbra Collaboration (ZCS) 9.0 and 10.0 and 10.1. A stored cross-site scripting (XSS) vulnerability exists in the Classic Web Client due to insufficient…

+53008 more

references (6)

External citations — patches, advisories, analysis.

scry

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