CVE-2026-64565 Input: ims-pcu - fix heap-buffer-overflow in ims_pcu_process_data()
A heap buffer overflow in the Linux kernel ims-pcu driver allows local attackers with physical access to execute arbitrary code via a malicious USB device.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-64565?
CVE-2026-64565 is a memory corruption vulnerability in Linux, published on 4 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
In the Linux kernel, the following vulnerability has been resolved:
Input: ims-pcu - fix heap-buffer-overflow in ims_pcu_process_data()
The `ims_pcu_process_data()` processes incoming URB data byte by byte. However, it fails to check if the `read_pos` index exceeds IMS_PCU_BUF_SIZE.
If a malicious USB device sends a packet larger than IMS_PCU_BUF_SIZE, `read_pos` will increment indefinitely. Moreover, since `read_pos` is located immediately after `read_buf`, the attacker can overwrite `read_pos` itself to arbitrarily control the index.
This manipulated `read_pos` is subsequently used in `ims_pcu_handle_response()` to copy data into `cmd_buf`, leading to a heap buffer overflow.
Specifically, an attacker can overwrite the `cmd_done.wait.head` located at offset 136 relative to `cmd_buf` in the `ims_pcu_handle_response()`. Consequently, when the driver calls `complete(&pcu->cmd_done)`, it triggers a control flow hijack by using the manipulated pointer.
Fix this by adding a bounds check for `read_pos` before writing to `read_buf`. If the packet is too long, discard it, log a warning, and reset the parser state.
[dtor: factor out resetting packet state, reset checksum as well]
Which versions are affected by CVE-2026-64565?
How do I fix CVE-2026-64565?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-64565 being exploited?
There is no known exploitation of CVE-2026-64565 in the wild and no public exploit code.
Sources
Also known as AZL-94401, BELL-CVE-2026-64565, DEBIAN-CVE-2026-64565, GHSA-36cq-f2m4-833w, UBUNTU-CVE-2026-64565.