CVEvulnerability
CVE-2026-64565
- Status
- Received
- Published
- 2026-08-04
- Last modified
- 2026-10-23
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
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]
References
- https://git.kernel.org/stable/c/06cfff93fd40441292567b999091beab11c74504 git.kernel.org
- https://git.kernel.org/stable/c/3a801bc75ba1d121d0ed60e7234f93ba5651d87d git.kernel.org
- https://git.kernel.org/stable/c/40bbbf2e91fd60715525bf0405c67876af817edf git.kernel.org
- https://git.kernel.org/stable/c/875115b82c295277b81b6dfee7debc725f44e854 git.kernel.org
- https://git.kernel.org/stable/c/992a7173364dcf63e30012af43da3c2f279839f9 git.kernel.org
- https://git.kernel.org/stable/c/ca9f8c09845fb8c51b6d447f6428eecd1b8b0a49 git.kernel.org
- https://git.kernel.org/stable/c/d03a740e087de7dcb2a26dc1123377bd3d1d84ca git.kernel.org