Microsoft Windows up to Server 2022 Layer 2 Tunneling Protocol denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.8$0-$5k0.00

Summaryinfo

A vulnerability was found in Microsoft Windows. It has been classified as critical. This issue affects some unknown processing of the component Layer 2 Tunneling Protocol. The manipulation leads to denial of service. This vulnerability is traded as CVE-2023-21757. It is possible to initiate the attack remotely. There is no exploit available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability was found in Microsoft Windows (Operating System) and classified as critical. This issue affects an unknown code block of the component Layer 2 Tunneling Protocol. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability.

The weakness was shared 01/10/2023 as confirmed security guidance (Website). It is possible to read the advisory at portal.msrc.microsoft.com. The identification of this vulnerability is CVE-2023-21757. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/23/2025). The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-25924). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 6.8

VulDB Base Score: 7.5
VulDB Temp Score: 6.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.5
Vendor Vector (Microsoft): 🔍

CNA Base Score: 7.5
CNA Vector (Microsoft): 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Timelineinfo

12/13/2022 🔍
01/10/2023 +28 days 🔍
01/10/2023 +0 days 🔍
01/10/2023 +0 days 🔍
09/23/2025 +986 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: portal.msrc.microsoft.com
Status: Confirmed

CVE: CVE-2023-21757 (🔍)
GCVE (CVE): GCVE-0-2023-21757
GCVE (VulDB): GCVE-100-217859
EUVD: 🔍
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 01/10/2023 21:39
Updated: 09/23/2025 06:58
Changes: 01/10/2023 21:39 (10), 01/10/2023 21:40 (26), 01/10/2023 21:43 (19), 01/31/2023 19:40 (2), 01/31/2023 19:47 (10), 09/23/2025 06:58 (16)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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