CVE-2026-99097 tee: shm: reject zero-sized allocations in tee_dyn_shm_alloc_helper()
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-99097?
CVE-2026-99097 is a vulnerability in Linux, published on 26 Oct 2026.
Official description
In the Linux kernel, the following vulnerability has been resolved:
tee: shm: reject zero-sized allocations in tee_dyn_shm_alloc_helper()
tee_dyn_shm_alloc_helper() derives nr_pages from a caller-supplied size and passes it to alloc_pages_exact() without checking it. For size == 0 nr_pages is 0, and alloc_pages_exact(0) calls get_order(0), which is documented as undefined and returns BITS_PER_LONG - PAGE_SHIFT. The page allocator then trips its order > MAX_PAGE_ORDER warning and fails the allocation; on a panic_on_warn kernel that ends the boot.
This can be triggered by TEE_IOC_SHM_ALLOC with struct tee_ioctl_shm_alloc_data where size is 0.
Reject a zero page count, as register_shm_helper() already does for the register path.
Which versions are affected by CVE-2026-99097?
How do I fix CVE-2026-99097?
Upgrade to a fixed version.
Is CVE-2026-99097 being exploited?
There is no known exploitation of CVE-2026-99097 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-99097, DEBIAN-CVE-2026-99097, GHSA-6fpw-5chx-rgh9, UBUNTU-CVE-2026-99097.