Host-memory disclosure via unchecked TFTP packet length
Published Jun 15, 2021 · Updated Aug 3, 2024
Out-of-bounds read in Libslirp Project libslirp before 4.6.0 allows guest OS users to disclose host memory through a short UDP packet. The tftp_input function casts the packet buffer to a tftp_t structure and reads its opcode without first confirming that the buffer contains the complete header. Exploitation requires control of a guest using SLiRP TFTP networking; successful requests return bytes outside the packet buffer without modifying host data or interrupting service.
Summary
What happened
Out-of-bounds read in Libslirp Project libslirp before 4.6.0 allows guest OS users to disclose host memory through a short UDP packet. The tftp_input function casts the packet buffer to a tftp_t structure and reads its opcode without first confirming that the buffer contains the complete header. Exploitation requires control of a guest using SLiRP TFTP networking; successful requests return bytes outside the packet buffer without modifying host data or interrupting service.
The record
- CVE
- CVE-2021-3595
- Published
- Jun 15, 2021
- Updated
- Aug 3, 2024
- Vendor
- Libslirp Project
- Product
- libslirp
- Classifications
- CWE-824, T1005
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 15, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 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=libslirp 4.6.0
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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