Microsoft Windows up to Server 2025 DNS race condition

Summaryinfo

A vulnerability, which was classified as very critical, has been found in Microsoft Windows up to Server 2025. This issue affects some unknown processing of the component DNS. Performing a manipulation results in race condition. This vulnerability is reported as CVE-2026-62820. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability classified as very critical has been found in Microsoft Windows up to Server 2025. This affects an unknown functionality of the component DNS. The manipulation with an unknown input leads to a race condition vulnerability. CWE is classifying the issue as CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows DNS allows an unauthorized attacker to execute code over a network.

The advisory is shared at msrc.microsoft.com. This vulnerability is uniquely identified as CVE-2026-62820 since 07/14/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/11/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Operating System

Vendor

• Microsoft

Name

• Windows

Version

• 10 1607
• 10 1809
• Server 2016
• Server 2019
• Server 2022
• Server 2025

License

• commercial

Website

• Vendor: https://www.microsoft.com/
• Product: https://www.microsoft.com/en-us/windows

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Discussion