CVE-2021-37860

lowpriority · track · 24EPSS 0.006 · 50 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.63% (50th) EPSS

CVSS 2.6 · low

Is it mine?

4 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · osv · nvd

EPSS · scored 2026-10-27

Mattermost 5.38 and earlier fails to sufficiently sanitize clipboard contents, which allows a user-assisted attacker to inject arbitrary web script in product deployments that explicitly disable the default CSP.

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⚠ sources disagree · low–medium · 2.6–6.1

v2.02.6lowAV:N/AC:H/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 4.9 · 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

v3.13.7lowCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:Nsecondary · ENISA EU

v3.13.7lowCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:Nsecondary · responsibledisclosure@mattermost.comexploitability 1.2 · impact 2.5

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nsecondary · OSV

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-79USprimaryCWE-79US

affected products (4)

Products and version ranges known to be affected.

Mattermost Mattermost≤ unspecified ≤5.38enisa_euvdEU
mattermost mattermost≤ 5.38nvdUScpe:2.3:a:mattermost:mattermost:*:*:*:*:*:*:*:*
Go github.com/mattermost/mattermost-serverall versionsosvUSpkg:golang/github.com/mattermost/mattermost-server
Go github.com/mattermost/mattermost-server/v5< 5.39.0osvUSpkg:golang/github.com/mattermost/mattermost-server/v5

advisories (2)

Vendor and ecosystem advisories describing this.

GHSA-hv5f-73mr-7vvjCross-site Scripting in Mattermost2021-09-23ghsa · osvUS
Mattermost 5.38 and earlier fails to sufficiently sanitize clipboard contents, which allows a user-assisted attacker to inject arbitrary web script in product deployments that explicitly disable the default CSP.
GO-2022-0604Cross-site Scripting in Mattermost in github.com/mattermost/mattermost-server2024-08-21vendor · osvUS
Cross-site Scripting in Mattermost in github.com/mattermost/mattermost-server

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv nvd NVD CVE.org MITRE

published 2021-09-22modified 2026-06-17

related (53,009)

Related entries.

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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…
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+53004 more

references (5)

External citations — patches, advisories, analysis.

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