Kernel memory corruption via oversized shrink copy
Published Jun 8, 2026 · Updated Jun 8, 2026
An out-of-bounds write in Linux Kernel 6.18.0 through 6.18.26 corrupts kernel memory during a forced shrink reallocation. The need_realloc path in vrealloc_node_align() allocates size bytes but memcpy() copies old_size bytes even when the new allocation is smaller. The path requires __GFP_THISNODE, and Ubuntu reports that no in-tree caller supplies the flag, so current in-tree callers cannot trigger the write; affected versions also include 6.19.0 through 7.0.3.
Summary
What happened
An out-of-bounds write in Linux Kernel 6.18.0 through 6.18.26 corrupts kernel memory during a forced shrink reallocation. The need_realloc path in vrealloc_node_align() allocates size bytes but memcpy() copies old_size bytes even when the new allocation is smaller. The path requires __GFP_THISNODE, and Ubuntu reports that no in-tree caller supplies the flag, so current in-tree callers cannot trigger the write; affected versions also include 6.19.0 through 7.0.3.
The record
- CVE
- CVE-2026-46281
- Published
- Jun 8, 2026
- Updated
- Jun 8, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-787
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 8, 2026CVE publishedPublication date reported by the CVE source.
- Jun 8, 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=4c5d3365882dbbc0784688784904f440d7a4c0f1 <82d1f01292d3f09bf063f829f8ab8de12b4280a1
- Affected versionversion=4c5d3365882dbbc0784688784904f440d7a4c0f1 <b281adf71f786c325eb6d6d1582d4d05313438a8
- Affected versionversion=4c5d3365882dbbc0784688784904f440d7a4c0f1 <e9b057a44deff4c59c13f44672a5cc74dcd57522
- Affected versionversion=6.18
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What is affected?
Published CVSS scores
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Attacks
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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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