vulnerability
Microsoft Windows: CVE-2023-50868: MITRE: CVE-2023-50868 NSEC3 closest encloser proof can exhaust CPU
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 8 | (AV:N/AC:L/Au:N/C:N/I:N/A:C) | Jun 11, 2024 | Jun 11, 2024 | Sep 16, 2025 |
Severity
8
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:C)
Published
Jun 11, 2024
Added
Jun 11, 2024
Modified
Sep 16, 2025
Description
The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance is skipped) allows remote attackers to cause a denial of service (CPU consumption for SHA-1 computations) via DNSSEC responses in a random subdomain attack, aka the "NSEC3" issue. The RFC 5155 specification implies that an algorithm must perform thousands of iterations of a hash function in certain situations.
Solutions
microsoft-windows-windows_server_2012-kb5039260microsoft-windows-windows_server_2012_r2-kb5039294microsoft-windows-windows_server_2016-1607-kb5039214microsoft-windows-windows_server_2019-1809-kb5039217microsoft-windows-windows_server_2022-21h2-kb5039227microsoft-windows-windows_server_2022-22h2-kb5039227microsoft-windows-windows_server_2022-23h2-kb5039236
References
- CVE-2023-50868
- https://attackerkb.com/topics/CVE-2023-50868
- CWE-400
- https://support.microsoft.com/help/5039214
- https://support.microsoft.com/help/5039217
- https://support.microsoft.com/help/5039227
- https://support.microsoft.com/help/5039236
- https://support.microsoft.com/help/5039260
- https://support.microsoft.com/help/5039294
Rapid7 Labs
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