Client memory disclosure via ClearCodec bounds read
Published May 29, 2020 · Updated Aug 4, 2024
Out-of-bounds read in FreeRDP through 2.0.0 allows remote authenticated users to read client memory via crafted ClearCodec /gfx data. The clear_decompress_subcode_rlex routine reads beyond the valid buffer while decoding server-supplied RLE graphics, rendering the leaked bytes as on-screen color. Exploitation requires connecting a client with /gfx enabled to an attacker-controlled or compromised RDP server; the demonstrated consequence is limited memory disclosure and possible client instability.
Summary
What happened
Out-of-bounds read in FreeRDP through 2.0.0 allows remote authenticated users to read client memory via crafted ClearCodec /gfx data. The clear_decompress_subcode_rlex routine reads beyond the valid buffer while decoding server-supplied RLE graphics, rendering the leaked bytes as on-screen color. Exploitation requires connecting a client with /gfx enabled to an attacker-controlled or compromised RDP server; the demonstrated consequence is limited memory disclosure and possible client instability.
The record
- CVE
- CVE-2020-11040
- Published
- May 29, 2020
- Updated
- Aug 4, 2024
- Vendor
- FreeRDP
- Product
- FreeRDP
- Classifications
- CWE-125
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- May 29, 2020CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record 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=<= 2.0.0
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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