Unauthenticated uninitialized-memory disclosure via ONCRPC XDR
Published Aug 12, 2021 · Updated Aug 10, 2026
Information disclosure in Microsoft Windows Services for NFS allows remote attackers to read uninitialized memory through ONCRPC XDR requests. The ONCRPC XDR driver returns uninitialized memory in a response, although Microsoft has not published the precise function or field involved. No authentication or user interaction is required; successful exploitation exposes memory contents without altering data or interrupting service.
Summary
What happened
Information disclosure in Microsoft Windows Services for NFS allows remote attackers to read uninitialized memory through ONCRPC XDR requests. The ONCRPC XDR driver returns uninitialized memory in a response, although Microsoft has not published the precise function or field involved. No authentication or user interaction is required; successful exploitation exposes memory contents without altering data or interrupting service.
The record
- CVE
- CVE-2021-26433
- Published
- Aug 12, 2021
- Updated
- Aug 10, 2026
- Vendor
- Microsoft
- Product
- Windows 10 Version 1507
- Classifications
- Unavailable
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 12, 2021CVE publishedPublication date reported by the CVE source.
- Aug 10, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=10.0.10240.0 <10.0.10240.19022
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
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Technologies
Your stack
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Your stack
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