Microsoft Windows up to Server 2022 Lightweight Directory Access 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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7.4$0-$5k0.00

Summaryinfo

A vulnerability was found in Microsoft Windows and classified as critical. Impacted is an unknown function of the component Lightweight Directory Access Protocol. Executing a manipulation can lead to denial of service. This vulnerability is handled as CVE-2023-21557. The attack can be executed remotely. There is not any exploit available. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability was found in Microsoft Windows (Operating System). It has been declared as critical. This vulnerability affects an unknown code of the component Lightweight Directory Access Protocol. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability.

The weakness was released 01/10/2023 as confirmed security guidance (Website). The advisory is shared for download at portal.msrc.microsoft.com. This vulnerability was named CVE-2023-21557. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 09/19/2025). The MITRE ATT&CK project declares the attack technique as T1499.

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-2023-25724). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.4

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

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

NVD Base Score: 9.1
NVD Vector: 🔍

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

CVSSv2info

AVACAuCIA
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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

12/01/2022 🔍
01/10/2023 +40 days 🔍
01/10/2023 +0 days 🔍
01/10/2023 +0 days 🔍
09/19/2025 +983 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

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

CVE: CVE-2023-21557 (🔍)
GCVE (CVE): GCVE-0-2023-21557
GCVE (VulDB): GCVE-100-217816
EUVD: 🔍
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 01/10/2023 21:09
Updated: 09/19/2025 20:29
Changes: 01/10/2023 21:09 (18), 01/10/2023 21:10 (18), 01/10/2023 21:13 (19), 01/31/2023 12:02 (2), 01/31/2023 12:10 (20), 09/19/2025 20:29 (16)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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