CVE-2021-24099

Skype for Business and Lync Denial of Service Vulnerability

View on CVE.org

Published Feb 25, 2021 CVSS 3.1 · 6.5 Medium EPSS 3.2% KEV · Not listed

Description

Skype for Business and Lync Denial of Service Vulnerability

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Microsoft

Skype for Business Server 2019 CU2

affected

Version	Status	Constraints
`7.0.0`	affected	< publication

Microsoft

Skype for Business Server 2015 CU 8

affected

Version	Status	Constraints
`2015 CU 8`	affected	< publication

Microsoft

Microsoft Lync Server 2013

affected

Version	Status	Constraints
`0`	affected	< publication

Configuration 1 [-]

OR	cpe:2.3:a:microsoft:lync_server:2013:::::::*
	cpe:2.3:a:microsoft:skype_for_business_server:2015:cu8::::::
	cpe:2.3:a:microsoft:skype_for_business_server:2019:cu2::::::

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
EUVD	EUVD-2021-11015	Skype for Business and Lync Denial of Service Vulnerability

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication Single

Confidentiality Impact None

Integrity Impact None

Availability Impact Partial

This CVE is not in the KEV list.

Exploit prediction score: 3.2% (3.201% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-24099

History

No history.

Subscriptions

Microsoft Lync Server Skype For Business Server

Weaknesses

NVD-CWE-noinfo

Sources

CVE record Updated: Aug 3, 2024, 7:21 PM

Status: PUBLISHED
Assigner: microsoft
Published: Feb 25, 2021, 11:01 PM
Updated: Aug 3, 2024, 7:21 PM
Reserved: Jan 13, 2021, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 3:39 AM

Status: Modified
Published: Feb 25, 2021, 11:15 PM
Modified: Jun 17, 2026, 3:39 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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