CVE-2026-34339: Windows Lightweight Directory Access Protocol (LDAP) Denial of Service Vulnerability
Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an authorized attacker to deny service locally.
Other sources
Windows Lightweight Directory Access Protocol (LDAP) Denial of Service Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.28000.2113Patch KB5089548 - Upgrade
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Fixed in 10.0.14393.9140Patch KB5087537 - Upgrade
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Fixed in 10.0.26100.32860Fixed in 10.0.26100.32772Patch KB5087423 - Upgrade
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Fixed in 10.0.25398.2330Patch KB5087541 - Upgrade
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Fixed in 10.0.26100.8457Fixed in 10.0.26100.8390Patch KB5089466 - Upgrade
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Fixed in 10.0.22631.7079Patch KB5087420 - Upgrade
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Fixed in 10.0.22631.7219Patch KB5093998 - Upgrade
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Fixed in 10.0.26200.8457Fixed in 10.0.26200.8390Patch KB5089466 - Upgrade
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Fixed in 10.0.19045.7417Patch KB5094127 - Upgrade
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Fixed in 10.0.19044.7291Patch KB5087544 - Upgrade
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Fixed in 10.0.20348.5139Fixed in 10.0.20348.5074Patch KB5087424 - Upgrade
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Fixed in 10.0.17763.8755Patch KB5087538
Event History
Frequently Asked Questions
What is the severity of CVE-2026-34339?
The severity of CVE-2026-34339 is categorized as a denial of service vulnerability affecting Windows Lightweight Directory Access Protocol (LDAP).
How do I fix CVE-2026-34339?
To fix CVE-2026-34339, apply the latest security patches and updates provided by Microsoft for the affected Windows versions.
Which versions of Windows are affected by CVE-2026-34339?
CVE-2026-34339 affects multiple versions of Windows, including several editions of Windows Server 2016, Windows Server 2022, Windows 10, and Windows 11.
What type of attack does CVE-2026-34339 facilitate?
CVE-2026-34339 allows an authorized attacker to cause a denial of service by exploiting a null pointer dereference in Windows LDAP.
Can CVE-2026-34339 be exploited remotely?
No, CVE-2026-34339 requires local access, meaning the attacker must have some level of local access to the system to exploit it.