CVE-2026-64302
x86/mm: Fix freeing of PMD-sized vmemmap pages
Description
In the Linux kernel, the following vulnerability has been resolved: x86/mm: Fix freeing of PMD-sized vmemmap pages Commit bf9e4e30f353 ("x86/mm: use pagetable_free()"), switched from freeing non-boot page tables through __free_pages() to pagetable_free(). However, the function is also called to free vmemmap pages. Given that vmemmap pages are not page tables, already the page_ptdesc(page) is wrong. But worse, pagetable_free() calls: __free_pages(page, compound_order(page)); Since vmemmap pages are not compound pages (see vmemmap_alloc_block()) -- except for HVO, which doesn't apply here -- only first page of a PMD-sized vmemmap page is freed, leaking the other ones. Fix it by properly decoupling pagetable and vmemmap freeing. free_pagetable() no longer has to mess with SECTION_INFO, as only the vmemmap is marked like that in register_page_bootmem_memmap(). The indentation in remove_pmd_table() is messed up. Fix that while touching it. Bootmem info handling will soon be fixed up. For now, handle it similar to free_pagetable(), just avoiding the ifdef. [ dhansen: changelog munging. More imperative voice ]
INFO
Published Date :
July 25, 2026, 10:17 a.m.
Last Modified :
Aug. 17, 2026, 5:17 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Apply the Linux kernel patch.
- Update the Linux kernel.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-64302.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-64302 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-64302
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-64302 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-64302 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 17, 2026
Action Type Old Value New Value Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'a1593c90896babf33e947910c7aecb9f50bab993', 'lessThan': 'add1e4112e00b619614784bf630aeebfdefa23e1', 'versionType': 'git'}, {'status': 'affected', 'version': 'bf9e4e30f3538391745a99bc2268ec4f5e4a401e', 'lessThan': '03f6ecbc446c33b38fd452cd3c494092a8116967', 'versionType': 'git'}, {'status': 'affected', 'version': 'bf9e4e30f3538391745a99bc2268ec4f5e4a401e', 'lessThan': '39406c05f8f150f1685839acd38ffdd69ff92031', 'versionType': 'git'}, {'status': 'affected', 'version': '6.18.7', 'lessThan': '6.18.39', 'versionType': 'semver'}], 'programFiles': ['arch/x86/mm/init_64.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.19'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.19', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.39', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.4', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['arch/x86/mm/init_64.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'a1593c90896babf33e947910c7aecb9f50bab993', 'lessThan': 'add1e4112e00b619614784bf630aeebfdefa23e1', 'versionType': 'git'}, {'status': 'affected', 'version': 'bf9e4e30f3538391745a99bc2268ec4f5e4a401e', 'lessThan': '03f6ecbc446c33b38fd452cd3c494092a8116967', 'versionType': 'git'}, {'status': 'affected', 'version': 'bf9e4e30f3538391745a99bc2268ec4f5e4a401e', 'lessThan': '39406c05f8f150f1685839acd38ffdd69ff92031', 'versionType': 'git'}, {'status': 'affected', 'version': '6.18.7', 'lessThan': '6.18.39', 'versionType': 'semver'}], 'programFiles': ['arch/x86/mm/init_64.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.19'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.19', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.39', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.4', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['arch/x86/mm/init_64.c'], 'defaultStatus': 'affected'}] -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 25, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'a1593c90896babf33e947910c7aecb9f50bab993', 'lessThan': 'add1e4112e00b619614784bf630aeebfdefa23e1', 'versionType': 'git'}, {'status': 'affected', 'version': 'bf9e4e30f3538391745a99bc2268ec4f5e4a401e', 'lessThan': '03f6ecbc446c33b38fd452cd3c494092a8116967', 'versionType': 'git'}, {'status': 'affected', 'version': 'bf9e4e30f3538391745a99bc2268ec4f5e4a401e', 'lessThan': '39406c05f8f150f1685839acd38ffdd69ff92031', 'versionType': 'git'}, {'status': 'affected', 'version': '6.18.7', 'lessThan': '6.18.39', 'versionType': 'semver'}], 'programFiles': ['arch/x86/mm/init_64.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.19'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.19', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.39', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.4', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['arch/x86/mm/init_64.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: x86/mm: Fix freeing of PMD-sized vmemmap pages Commit bf9e4e30f353 ("x86/mm: use pagetable_free()"), switched from freeing non-boot page tables through __free_pages() to pagetable_free(). However, the function is also called to free vmemmap pages. Given that vmemmap pages are not page tables, already the page_ptdesc(page) is wrong. But worse, pagetable_free() calls: __free_pages(page, compound_order(page)); Since vmemmap pages are not compound pages (see vmemmap_alloc_block()) -- except for HVO, which doesn't apply here -- only first page of a PMD-sized vmemmap page is freed, leaking the other ones. Fix it by properly decoupling pagetable and vmemmap freeing. free_pagetable() no longer has to mess with SECTION_INFO, as only the vmemmap is marked like that in register_page_bootmem_memmap(). The indentation in remove_pmd_table() is messed up. Fix that while touching it. Bootmem info handling will soon be fixed up. For now, handle it similar to free_pagetable(), just avoiding the ifdef. [ dhansen: changelog munging. More imperative voice ] Added Reference https://git.kernel.org/stable/c/03f6ecbc446c33b38fd452cd3c494092a8116967 Added Reference https://git.kernel.org/stable/c/39406c05f8f150f1685839acd38ffdd69ff92031 Added Reference https://git.kernel.org/stable/c/add1e4112e00b619614784bf630aeebfdefa23e1