Arbitrary code execution via wrapped thumbnail allocation
Published Aug 25, 2026 · Updated Aug 25, 2026
Heap buffer overflow in libtiff's thumbnail tool allows local users to execute arbitrary code through oversized dimensions. The tool parses width and height with strtoul without upper-bound validation, then multiplies the uint32_t values when allocating the thumbnail buffer, so wraparound leaves setrow writing beyond the allocation. Exploitation requires local control of the command dimensions and TIFF input; successful corruption executes code with the utility's privileges.
Summary
What happened
Heap buffer overflow in libtiff's thumbnail tool allows local users to execute arbitrary code through oversized dimensions. The tool parses width and height with strtoul without upper-bound validation, then multiplies the uint32_t values when allocating the thumbnail buffer, so wraparound leaves setrow writing beyond the allocation. Exploitation requires local control of the command dimensions and TIFF input; successful corruption executes code with the utility's privileges.
The record
- CVE
- CVE-2026-52491
- Published
- Aug 25, 2026
- Updated
- Aug 25, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- T1203
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Aug 25, 2026CVE publishedPublication date reported by the CVE source.
- Aug 25, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
- libtiff thumbnail heap-buffer-overflow proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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