Memory corruption via truncated OpenType FeatureList
Published Aug 31, 2026 · Updated Sep 4, 2026
Buffer overflow in OpenType font handling in WebKitGTK allows remote attackers to corrupt memory through malicious web content. FeatureList::findFeature validates only the start of each FeatureRecord before reading fields that extend to the next record, allowing a truncated array to drive an out-of-bounds read. Exploitation requires a user to load attacker-controlled content; the resulting corruption can crash the renderer or compromise its process.
Summary
What happened
Buffer overflow in OpenType font handling in WebKitGTK allows remote attackers to corrupt memory through malicious web content. FeatureList::findFeature validates only the start of each FeatureRecord before reading fields that extend to the next record, allowing a truncated array to drive an out-of-bounds read. Exploitation requires a user to load attacker-controlled content; the resulting corruption can crash the renderer or compromise its process.
The record
- CVE
- CVE-2026-83596
- Published
- Aug 31, 2026
- Updated
- Sep 4, 2026
- Vendor
- The WebKitGTK Team
- Product
- WebKitGTK
- Classifications
- CWE-120, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 31, 2026CVE publishedPublication date reported by the CVE source.
- Sep 4, 2026Record 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=1.10.0 <*
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What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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