Client crash via unchecked ZGFX segment lengths
Published Nov 16, 2022 · Updated Nov 3, 2025
Out-of-bounds read in FreeRDP before 2.9.0 allows remote attackers controlling an RDP server to crash clients via crafted ZGFX data. The zgfx_decompress_segment function advances and copies input without first rejecting undersized segments or reads beyond the remaining compressed bits. Exploitation requires a client to connect to an attacker-controlled server and process its graphics stream; the bounded reported consequence is a client crash.
Summary
What happened
Out-of-bounds read in FreeRDP before 2.9.0 allows remote attackers controlling an RDP server to crash clients via crafted ZGFX data. The zgfx_decompress_segment function advances and copies input without first rejecting undersized segments or reads beyond the remaining compressed bits. Exploitation requires a client to connect to an attacker-controlled server and process its graphics stream; the bounded reported consequence is a client crash.
The record
- CVE
- CVE-2022-39316
- Published
- Nov 16, 2022
- Updated
- Nov 3, 2025
- Vendor
- FreeRDP
- Product
- FreeRDP
- Classifications
- CWE-125, T1499
- Attack vector
- network
- Privileges
- Unavailable
Timeline
How it unfolded
- Nov 16, 2022CVE 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?
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- Affected versionversion=< 2.9.0
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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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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