Kernel heap disclosure via undersized NTFS3 EA record
Published Sep 16, 2026 · Updated Sep 16, 2026
Out-of-bounds read in Linux 5.15.121 through 5.15.220, 6.1.40 through 6.1.187, and 6.2 allows local users to read kernel heap memory. In fs/ntfs3/xattr.c, ntfs_read_ea() accepts a nonzero ef->size that does not cover name_len plus elength, and ntfs_get_ea() then copies the attacker-controlled value length from the undersized allocation. Exploitation requires access to a crafted NTFS image and a getxattr() call with a sufficiently large output buffer; the demonstrated consequence is disclosure of heap contents to userspace.
Summary
What happened
Out-of-bounds read in Linux 5.15.121 through 5.15.220, 6.1.40 through 6.1.187, and 6.2 allows local users to read kernel heap memory. In fs/ntfs3/xattr.c, ntfs_read_ea() accepts a nonzero ef->size that does not cover name_len plus elength, and ntfs_get_ea() then copies the attacker-controlled value length from the undersized allocation. Exploitation requires access to a crafted NTFS image and a getxattr() call with a sufficiently large output buffer; the demonstrated consequence is disclosure of heap contents to userspace.
The record
- CVE
- CVE-2026-89779
- Published
- Sep 16, 2026
- Updated
- Sep 16, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1005
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 16, 2026CVE publishedPublication date reported by the CVE source.
- Sep 16, 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=000a9a72efa4a9df289bab9c9e8ba1639c72e0d6 <28a924c7e67e6d71abeb04860b61166fecb027fc
- Affected versionversion=0e8235d28f3a0e9eda9f02ff67ee566d5f42b66b <077df8464cf24f8ffc82fb6efec2ae600686e699
- Affected versionversion=0e8235d28f3a0e9eda9f02ff67ee566d5f42b66b <aab1880058ac767d3ea9388a9a7221c776c22c44
- Affected versionversion=0e8235d28f3a0e9eda9f02ff67ee566d5f42b66b <c22f91d82cb9a29d22bdffdce6c803467984ad0c
- Affected versionversion=0e8235d28f3a0e9eda9f02ff67ee566d5f42b66b <c8a109c9e23a2c7fd548473dde728b2cb8188146
- Affected versionversion=0e8235d28f3a0e9eda9f02ff67ee566d5f42b66b <d585ed08308909c7e6fefb4e8a258aeb29b19ff9
- Affected versionversion=333feb7ba84f69f9b423422417aaac54fd9e7c84 <b27e68ad818a4ca2cef8f35f97e75d756714c818
- Affected versionversion=5.15.121 <5.15.221
- Affected versionversion=6.1.40 <6.1.188
- Affected versionversion=6.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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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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