Memory corruption via unchecked lcns_follow length
Published Jul 27, 2026 · Updated Jul 27, 2026
Out-of-bounds memory access in Linux Kernel allows local users to corrupt kernel memory by supplying a malformed NTFS filesystem image. In fs/ntfs3/fslog.c, log_replay() trusts the on-disk lcns_follow count when sizing memmove() during version 0 restart-table conversion, allowing the copy and later page_lcns iteration to exceed the allocated buffer. Triggering requires the kernel to process attacker-controlled NTFS metadata and can destabilize or crash the system.
Summary
What happened
Out-of-bounds memory access in Linux Kernel allows local users to corrupt kernel memory by supplying a malformed NTFS filesystem image. In fs/ntfs3/fslog.c, log_replay() trusts the on-disk lcns_follow count when sizing memmove() during version 0 restart-table conversion, allowing the copy and later page_lcns iteration to exceed the allocated buffer. Triggering requires the kernel to process attacker-controlled NTFS metadata and can destabilize or crash the system.
The record
- CVE
- CVE-2026-64533
- Published
- Jul 27, 2026
- Updated
- Jul 27, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- T1499.004
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 27, 2026CVE publishedPublication date reported by the CVE source.
- Jul 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=5.15
- Affected versionversion=b46acd6a6a627d876898e1c84d3f84902264b445 <159f694d682e4215b3822ae31ed3a4631628fe55
- Affected versionversion=b46acd6a6a627d876898e1c84d3f84902264b445 <32b9f8733feb241627fa5f564b1a99b5cae974c5
- Affected versionversion=b46acd6a6a627d876898e1c84d3f84902264b445 <57c071e2c4f30b9c6f5aacb6679aab1269fbae99
- Affected versionversion=b46acd6a6a627d876898e1c84d3f84902264b445 <6a4c53a2e26a865565bd6a460961e8d6fcb32329
- Affected versionversion=b46acd6a6a627d876898e1c84d3f84902264b445 <7adb38279812c9c06b0e3fa7382f4d7887f3fa2d
- Affected versionversion=b46acd6a6a627d876898e1c84d3f84902264b445 <ca343a99806b4fc8e27c48f08be3445c5fcd1445
- Affected versionversion=b46acd6a6a627d876898e1c84d3f84902264b445 <ddfc8683e1a627dbf1b83bacf8961443dd654258
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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