Memory disclosure via unbounded Huffman table index
Published Oct 15, 2021 · Updated Aug 3, 2024
Out-of-bounds read in libmobi 0.7 and earlier allows context-dependent attackers to expose process memory via a corrupt MOBI file. The mobi_decompress_huffman_internal function increments code_length without bounding it before indexing the 33-entry mincode_table and maxcode_table arrays. A consuming application must parse attacker-controlled Huffman-compressed ebook data; successful exploitation exposes adjacent memory or crashes that process.
Summary
What happened
Out-of-bounds read in libmobi 0.7 and earlier allows context-dependent attackers to expose process memory via a corrupt MOBI file. The mobi_decompress_huffman_internal function increments code_length without bounding it before indexing the 33-entry mincode_table and maxcode_table arrays. A consuming application must parse attacker-controlled Huffman-compressed ebook data; successful exploitation exposes adjacent memory or crashes that process.
The record
- CVE
- CVE-2021-3881
- Published
- Oct 15, 2021
- Updated
- Aug 3, 2024
- Vendor
- bfabiszewski
- Product
- libmobi
- Classifications
- CWE-125, T1204.002
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Oct 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=unspecified <=0.7
What conditions does exploitation require?
What is affected?
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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