Local code execution via font subsetter overflow
Published Aug 11, 2026 · Updated Aug 25, 2026
Integer overflow in Windows Presentation Foundation in Microsoft .NET and .NET Framework allows local users to execute code via crafted font data. The WPF TrueType subsetter performs size and record-count arithmetic on untrusted CMap, sbit, kern, and related font tables, and wrapped values can invalidate bounds assumptions and lead to out-of-bounds memory access during font subsetting. Reachability depends on a local application path that loads attacker-controlled font-bearing content and on user interaction, so successful exploitation runs code in the vulnerable process rather than providing network-only reach.
Summary
What happened
Integer overflow in Windows Presentation Foundation in Microsoft .NET and .NET Framework allows local users to execute code via crafted font data. The WPF TrueType subsetter performs size and record-count arithmetic on untrusted CMap, sbit, kern, and related font tables, and wrapped values can invalidate bounds assumptions and lead to out-of-bounds memory access during font subsetting. Reachability depends on a local application path that loads attacker-controlled font-bearing content and on user interaction, so successful exploitation runs code in the vulnerable process rather than providing network-only reach.
The record
- CVE
- CVE-2026-62897
- Published
- Aug 11, 2026
- Updated
- Aug 25, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-190, T1204.002
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 11, 2026CVE publishedPublication date reported by the CVE source.
- Aug 25, 2026Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
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Published CVSS scores
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Attacks
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Weakness, pattern, technique
Public exploit references
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Technologies
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