CVE-2026-99097

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.

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EPSS — Exploit Prediction

0.0016

Probability of exploitation

0.06%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/65cb86860a80ffc6af897d53f5bd4b1733bca0ec https://git.kernel.org/stable/c/b7f925fd5226deb953c8dcdc9677d3fcc2717c00 https://git.kernel.org/stable/c/c2a97703359e25ec7ef8b2b0ef32fb3982add90a https://git.kernel.org/stable/c/e5dc7af9c3a5373ee7a84959126e7dfa9e4ad50d

Frequently Asked Questions

What is CVE-2026-99097? +

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.

How do I check if I'm vulnerable to CVE-2026-99097? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.