CVE-2026-99036
Received
Received - Intake
Race Condition in Linux Kernel Device Mapper
Vulnerability report for CVE-2026-99036, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-23
Last updated on: 2026-10-23
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
dm: fix reading free memory in do_resume
When do_resume calls dm_table_get_mode(new_map), the call is done without
holding any locks (it only holds a reference to the md). It may be
possible that another concurrent ioctl on the same device will swap table
after dm_swap_table and before dm_table_get_mode. In this case,
dm_table_get_mode(new_map) reads freed memory.
This race condition was triggered by syzbot.
This commit fixes the race by reading mode of the new table before
dm_swap_table. Note that new_map is also passed to dm_ima_need_measure,
but this function doesn't attempt to dereference it, so this call should
be safe.
Note that this is not a security bug because only root can trigger it and
the commonly used tools such as lvm or cryptsetup do not call the ioctls
concurrently, so that they can't trigger it acceidentally.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 |
| Linux | Linux | 0 |
| Linux | Linux | 0 |
| Linux | Linux | 0 |
| Linux | Linux | 0 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |