Service interruption via partial vmemmap page freeing
Published Jul 25, 2026 · Updated Jul 25, 2026
Resource leak in Linux Kernel 6.18.7 through 6.18.38 and 6.19 allows local users to interrupt service through vmemmap page teardown. pagetable_free() treats noncompound vmemmap memory as a page table and passes compound_order(page) to __free_pages(), so only the first page of each PMD-sized allocation is freed. Exploitation is limited to x86 systems where a high-privileged local user can repeatedly reach the affected teardown path, causing unreclaimed kernel memory and eventual service interruption.
Summary
What happened
Resource leak in Linux Kernel 6.18.7 through 6.18.38 and 6.19 allows local users to interrupt service through vmemmap page teardown. pagetable_free() treats noncompound vmemmap memory as a page table and passes compound_order(page) to __free_pages(), so only the first page of each PMD-sized allocation is freed. Exploitation is limited to x86 systems where a high-privileged local user can repeatedly reach the affected teardown path, causing unreclaimed kernel memory and eventual service interruption.
The record
- CVE
- CVE-2026-64302
- Published
- Jul 25, 2026
- Updated
- Jul 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- T1499
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Jul 25, 2026CVE publishedPublication date reported by the CVE source.
- Jul 25, 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=6.18.7 <6.18.39
- Affected versionversion=6.19
- Affected versionversion=a1593c90896babf33e947910c7aecb9f50bab993 <add1e4112e00b619614784bf630aeebfdefa23e1
- Affected versionversion=bf9e4e30f3538391745a99bc2268ec4f5e4a401e <03f6ecbc446c33b38fd452cd3c494092a8116967
- Affected versionversion=bf9e4e30f3538391745a99bc2268ec4f5e4a401e <39406c05f8f150f1685839acd38ffdd69ff92031
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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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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