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Mattermost CVE-2021-37860

MEDIUM
Cross-site Scripting (XSS) (CWE-79)
2021-09-22 responsibledisclosure@mattermost.com
6.1
CVSS 3.1 · NVD
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Severity by source

NVD PRIMARY
6.1 MEDIUM
AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

Lifecycle Timeline

1
CVE Published
Sep 22, 2021 - 17:15 nvd
MEDIUM 6.1

DescriptionNVD

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.

AnalysisAI

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. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

Technical ContextAI

This vulnerability is classified as Cross-Site Scripting (XSS) (CWE-79), which allows attackers to inject malicious scripts into web pages viewed by other users. 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. Affected products include: Mattermost.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Sanitize all user input, use Content-Security-Policy headers, encode output contextually (HTML, JS, URL). Use frameworks with built-in XSS protection.

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CVE-2021-37860 vulnerability details – vuln.today

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