CVE-2026-53210 tee: shm: fix shm leak in register_shm_helper()

What is CVE-2026-53210?

CVE-2026-53210 is a medium-severity denial of service vulnerability in Linux kernel, published on 25 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

tee: shm: fix shm leak in register_shm_helper()

register_shm_helper() allocates shm before calling iov_iter_npages(). If iov_iter_npages() returns 0, the function jumps to err_ctx_put and leaks shm.

This can be triggered by TEE_IOC_SHM_REGISTER with struct tee_ioctl_shm_register_data where length is 0.

Jump to err_free_shm instead.

Weakness: CWE-401

Which versions are affected by CVE-2026-53210?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-53210?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-53210 being exploited?

There is no known exploitation of CVE-2026-53210 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-53210, DEBIAN-CVE-2026-53210, GHSA-wfx4-v2wf-4gmp, ROOT-OS-UBUNTU-2404-CVE-2026-53210, UBUNTU-CVE-2026-53210.