HIGH 8.6 Microsoft
CVE-2025-40776
Birthday Attack against Resolvers supporting ECS
Microsoft Security Update 2026-Aug: Birthday Attack against Resolvers supporting ECS
Affected Products
- cbl2 bind 9.16.50-1
- azl3 bind 9.20.9-1 on Azure Linux 3.0
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-40776
- https://nvd.nist.gov/vuln/detail/CVE-2025-40776
This high severity vulnerability with a CVSS score of 8.6 was published on 2026-08-06 via Microsoft. Affected: cbl2 bind 9.16.50-1, azl3 bind 9.20.9-1 on Azure Linux 3.0.
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