Client crash via unchecked NSCodec plane data
Published Aug 31, 2023 · Updated Nov 3, 2025
Out-of-bounds read in FreeRDP clients before 2.11.0 and 3.0.0-beta1 through 3.0.0-beta2 allows remote attackers to crash the client. nsc_stream_initialize sets context->Planes to the remaining NSCodec stream, and nsc_rle_decompress_data advances and copies plane data without verifying that the stream contains the declared lengths. Exposure requires an affected client to decode crafted graphics data from a malicious or compromised RDP server; the FreeRDP proxy is unaffected.
Summary
What happened
Out-of-bounds read in FreeRDP clients before 2.11.0 and 3.0.0-beta1 through 3.0.0-beta2 allows remote attackers to crash the client. nsc_stream_initialize sets context->Planes to the remaining NSCodec stream, and nsc_rle_decompress_data advances and copies plane data without verifying that the stream contains the declared lengths. Exposure requires an affected client to decode crafted graphics data from a malicious or compromised RDP server; the FreeRDP proxy is unaffected.
The record
- CVE
- CVE-2023-39354
- Published
- Aug 31, 2023
- Updated
- Nov 3, 2025
- Vendor
- FreeRDP
- Product
- FreeRDP
- Classifications
- CWE-125
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 31, 2023CVE publishedPublication date reported by the CVE source.
- Nov 3, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 2.11.0
- Affected versionversion=>= 3.0.0-beta1, < 3.0.0-beta3
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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