Kernel memory corruption via overflow sentinel bypass
Published Jul 19, 2026 · Updated Jul 19, 2026
Out-of-bounds write in Linux Kernel 6.15 allows local users to corrupt kernel memory through the statmount system call. In statmount_mnt_idmap(), an unconditional count increment moves an overflow sentinel past the buffer size, defeating seq_has_overflowed() before statmount_string() appends a NUL byte out of bounds. Local low-privileged access is required; the bounded consequence is kernel memory corruption that can crash or destabilize the system.
Summary
What happened
Out-of-bounds write in Linux Kernel 6.15 allows local users to corrupt kernel memory through the statmount system call. In statmount_mnt_idmap(), an unconditional count increment moves an overflow sentinel past the buffer size, defeating seq_has_overflowed() before statmount_string() appends a NUL byte out of bounds. Local low-privileged access is required; the bounded consequence is kernel memory corruption that can crash or destabilize the system.
The record
- CVE
- CVE-2026-64074
- Published
- Jul 19, 2026
- Updated
- Jul 19, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-787, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 19, 2026CVE publishedPublication date reported by the CVE source.
- Jul 19, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=37c4a9590e1efcae7749682239fc22a330d2d325 <93614949dc86f068e3c32c32cf1ee2a2323177a7
- Affected versionversion=37c4a9590e1efcae7749682239fc22a330d2d325 <a3bf0f28d4ba16e1f35f8c983bb04426b87e2a78
- Affected versionversion=37c4a9590e1efcae7749682239fc22a330d2d325 <e37ea2c6f17f273813ea4e8e94c102591d598ce1
- Affected versionversion=6.15
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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