CVE-2026-6386
Last modified
CVE-2026-6386 is a medium-severity vulnerability rated 6.2/10 on the CVSS scale. In order to apply a particular protection key to an address range, the kernel must update the corresponding page table entries. The subroutine which handled this failed to take into account the presence of 1GB largepage mappings created using the shm_create_largepage(3) interface. EPSS estimates a 0.16% chance of exploitation in the next 30 days.
Description
In order to apply a particular protection key to an address range, the kernel must update the corresponding page table entries. The subroutine which handled this failed to take into account the presence of 1GB largepage mappings created using the shm_create_largepage(3) interface. In particular, it would always treat a page directory page entry as pointing to another page table page. The bug can be abused by an unprivileged user to cause pmap_pkru_update_range() to treat userspace memory as a page table page, and thus overwrite memory to which the application would otherwise not have access.
Metrics
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Freebsd | Freebsd | 13.5 |
| Freebsd | Freebsd | 14.3 |
| Freebsd | Freebsd | 14.4 |
| Freebsd | Freebsd | 15.0 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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