CVE-2026-74481
mm/page_reporting: use system_freezable_wq to fix UAF during suspend
Description
In the Linux kernel, the following vulnerability has been resolved: mm/page_reporting: use system_freezable_wq to fix UAF during suspend During PM freeze (e.g. S3 suspend or S4 hibernation), device drivers like virtio_balloon reset their underlying virtio devices and delete their virtqueues via vdev->config->del_vqs(). However, page reporting work (page_reporting_process) was scheduled on the global system_wq. Because system_wq lacks the WQ_FREEZABLE flag, the PM freezer skips it, leaving page_reporting_process active during suspend. If pages are freed into the buddy allocator while suspending (for example, when core MM invokes the balloon shrinker during S4 hibernation image saving), page reporting triggers virtballoon_free_page_report() on deleted virtqueues, resulting in a Use-After-Free / General Protection Fault: [ 196.795226] general protection fault, probably for non-canonical address 0xaa1436fe70dae6df: 0000 [#1] SMP NOPTI [ 196.825967] Workqueue: events page_reporting_process [ 196.831038] RIP: 0010:virtqueue_add_split+0x233/0x4c0 [virtio_ring] [ 196.927073] virtballoon_free_page_report+0x3a/0xe0 [virtio_balloon] [ 196.946943] page_reporting_process+0x370/0x4f0 Fix this by switching page reporting work to system_freezable_wq. This ensures that the PM freezer pauses page_reporting_process before device drivers destroy their reporting virtqueues. Because the reporting worker is frozen, memory reclamation/freeing (e.g. via shrinker execution) can safely return pages to MM during freeze without triggering unfrozen reporting work on deleted virtqueues. This aligns with the driver's existing design. The comment in virtballoon_freeze() states: /* * The workqueue is already frozen by the PM core before this * function is called. */ Testing: I have verified these fixes using Google’s virtualization infrastructure by running continuous suspend/resume iterations (40+ cycles) while churning memory using stress-ng (`stress-ng --vm 4 --vm-bytes 60% --timeout 1`) to constantly create free pages for the buddy allocator. We also set the `page_reporting_order` parameter to 0 to make the page reporting worker highly sensitive, forcing it to pick up any 4K free pages. This confirmed that the UAF crashes are no longer reproducible.
INFO
Published Date :
Aug. 15, 2026, 1:17 p.m.
Last Modified :
Aug. 19, 2026, 5:21 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Switch page reporting work to system_freezable_wq.
- Ensure PM freezer pauses page reporting.
- Test fixes with suspend/resume cycles.
- Churn memory to trigger reporting work.
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-2026-74481.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74481 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-2026-74481
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-2026-74481 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74481 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.
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CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 19, 2026
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/992f270fd808338fbae1f498a5e325e7e2e20368 Added Reference https://git.kernel.org/stable/c/a4c60046052777ca1dcc83fe3ece2a5136b301f1 Added Reference https://git.kernel.org/stable/c/b2c094e98f8bb823b3ae475f7169fe2091c40c6d Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'f978048326570047e8216e81a67f9c71ef2bb1b1', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': '450f35f4d5a682a0796757e52295df58ddb63bc9', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'b11907c905fa08eda925395f0724b7a409870f65', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': '0b45f6927a14914ff685fe0e6f9d11232a1e03df', 'versionType': 'git'}], 'programFiles': ['mm/page_reporting.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.7'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.7', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.151', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.103', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.44', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.8', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['mm/page_reporting.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'a4c60046052777ca1dcc83fe3ece2a5136b301f1', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'b2c094e98f8bb823b3ae475f7169fe2091c40c6d', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': '992f270fd808338fbae1f498a5e325e7e2e20368', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'f978048326570047e8216e81a67f9c71ef2bb1b1', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': '450f35f4d5a682a0796757e52295df58ddb63bc9', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'b11907c905fa08eda925395f0724b7a409870f65', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': '0b45f6927a14914ff685fe0e6f9d11232a1e03df', 'versionType': 'git'}], 'programFiles': ['mm/page_reporting.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.7'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.7', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.265', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.216', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.183', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.151', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.103', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.44', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.8', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['mm/page_reporting.c'], 'defaultStatus': 'affected'}] -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 17, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'f978048326570047e8216e81a67f9c71ef2bb1b1', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': '450f35f4d5a682a0796757e52295df58ddb63bc9', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'b11907c905fa08eda925395f0724b7a409870f65', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': '0b45f6927a14914ff685fe0e6f9d11232a1e03df', 'versionType': 'git'}], 'programFiles': ['mm/page_reporting.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.7'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.7', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.151', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.103', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.44', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.8', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc6', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['mm/page_reporting.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'f978048326570047e8216e81a67f9c71ef2bb1b1', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': '450f35f4d5a682a0796757e52295df58ddb63bc9', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'b11907c905fa08eda925395f0724b7a409870f65', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': '0b45f6927a14914ff685fe0e6f9d11232a1e03df', 'versionType': 'git'}], 'programFiles': ['mm/page_reporting.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.7'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.7', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.151', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.103', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.44', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.8', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['mm/page_reporting.c'], 'defaultStatus': 'affected'}] -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 15, 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': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'f978048326570047e8216e81a67f9c71ef2bb1b1', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': '450f35f4d5a682a0796757e52295df58ddb63bc9', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'b11907c905fa08eda925395f0724b7a409870f65', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': 'faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7', 'versionType': 'git'}, {'status': 'affected', 'version': '36e66c554b5c6a9d17a229faca7a61693527b0bd', 'lessThan': '0b45f6927a14914ff685fe0e6f9d11232a1e03df', 'versionType': 'git'}], 'programFiles': ['mm/page_reporting.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.7'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.7', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.151', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.103', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.44', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.8', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc6', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['mm/page_reporting.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: mm/page_reporting: use system_freezable_wq to fix UAF during suspend During PM freeze (e.g. S3 suspend or S4 hibernation), device drivers like virtio_balloon reset their underlying virtio devices and delete their virtqueues via vdev->config->del_vqs(). However, page reporting work (page_reporting_process) was scheduled on the global system_wq. Because system_wq lacks the WQ_FREEZABLE flag, the PM freezer skips it, leaving page_reporting_process active during suspend. If pages are freed into the buddy allocator while suspending (for example, when core MM invokes the balloon shrinker during S4 hibernation image saving), page reporting triggers virtballoon_free_page_report() on deleted virtqueues, resulting in a Use-After-Free / General Protection Fault: [ 196.795226] general protection fault, probably for non-canonical address 0xaa1436fe70dae6df: 0000 [#1] SMP NOPTI [ 196.825967] Workqueue: events page_reporting_process [ 196.831038] RIP: 0010:virtqueue_add_split+0x233/0x4c0 [virtio_ring] [ 196.927073] virtballoon_free_page_report+0x3a/0xe0 [virtio_balloon] [ 196.946943] page_reporting_process+0x370/0x4f0 Fix this by switching page reporting work to system_freezable_wq. This ensures that the PM freezer pauses page_reporting_process before device drivers destroy their reporting virtqueues. Because the reporting worker is frozen, memory reclamation/freeing (e.g. via shrinker execution) can safely return pages to MM during freeze without triggering unfrozen reporting work on deleted virtqueues. This aligns with the driver's existing design. The comment in virtballoon_freeze() states: /* * The workqueue is already frozen by the PM core before this * function is called. */ Testing: I have verified these fixes using Google’s virtualization infrastructure by running continuous suspend/resume iterations (40+ cycles) while churning memory using stress-ng (`stress-ng --vm 4 --vm-bytes 60% --timeout 1`) to constantly create free pages for the buddy allocator. We also set the `page_reporting_order` parameter to 0 to make the page reporting worker highly sensitive, forcing it to pick up any 4K free pages. This confirmed that the UAF crashes are no longer reproducible. Added Reference https://git.kernel.org/stable/c/0b45f6927a14914ff685fe0e6f9d11232a1e03df Added Reference https://git.kernel.org/stable/c/450f35f4d5a682a0796757e52295df58ddb63bc9 Added Reference https://git.kernel.org/stable/c/b11907c905fa08eda925395f0724b7a409870f65 Added Reference https://git.kernel.org/stable/c/f978048326570047e8216e81a67f9c71ef2bb1b1 Added Reference https://git.kernel.org/stable/c/faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7