Local memory corruption via empty fopen ccs value
Published Aug 27, 2026 · Updated Aug 27, 2026
Heap buffer overflow in GNU Project glibc 2.45 and earlier allows local users to corrupt memory through a crafted fopen mode string. The fopen mode parser mishandles an effectively empty value in the ,ccs= extension and writes beyond a heap allocation. Reachability requires an application to pass attacker-controlled ccs text into the mode argument, a pattern not found in common GNU/Linux distributions.
Summary
What happened
Heap buffer overflow in GNU Project glibc 2.45 and earlier allows local users to corrupt memory through a crafted fopen mode string. The fopen mode parser mishandles an effectively empty value in the ,ccs= extension and writes beyond a heap allocation. Reachability requires an application to pass attacker-controlled ccs text into the mode argument, a pattern not found in common GNU/Linux distributions.
The record
- CVE
- CVE-2026-18374
- Published
- Aug 27, 2026
- Updated
- Aug 27, 2026
- Vendor
- The GnuPG Project
- Product
- glibc
- Classifications
- CWE-787
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 27, 2026CVE publishedPublication date reported by the CVE source.
- Aug 27, 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=0 <2.45
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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