CVE-2026-46167
Summary
In the Linux kernel, the following vulnerability has been resolved: usb: usblp: fix uninitialized heap leak via LPGETSTATUS ioctl Just like in a previous problem in this driver, usblp_ctrl_msg() will collapse the usb_control_msg() return value to 0/-errno, discarding the actual number of bytes transferred. Ideally that short command should be detected and error out, but many printers are known to send "incorrect" responses back so we can't just do that. statusbuf is kmalloc(8) at probe time and never filled before the first LPGETSTATUS ioctl. usblp_read_status() requests 1 byte. If a malicious printer responds with zero bytes, *statusbuf is one byte of stale kmalloc heap, sign-extended into the local int status, which the LPGETSTATUS path then copy_to_user()s directly to the ioctl caller. Fix this all by just zapping out the memory buffer when allocated at probe time. If a later call does a short read, the data will be identical to what the device sent it the last time, so there is no "leak" of information happening.
Impact & exploitability
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected products we track (1)
Recommendation
Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.
Official patch: https://git.kernel.org/stable/c/087d97342c100138ea7d75a50977c9c2319f957b ↗
Additional information
- NVD record
- https://git.kernel.org/stable/c/087d97342c100138ea7d75a50977c9c2319f957bPatch
- https://git.kernel.org/stable/c/0f7c41314ebf17049917a452684db371babf711aPatch
- https://git.kernel.org/stable/c/6b0e7438e31c74b01514d31ff35c1e688c4baabaPatch
- https://git.kernel.org/stable/c/762a6ccf391db0d629e590a803a3a2231e17dd3fPatch
- https://git.kernel.org/stable/c/a502b997668401a6821501fc98b7f9220f9b6ff2Patch
- https://git.kernel.org/stable/c/b38e53cbfb9d84732e5984fbd73e128d592415c5Patch
- https://git.kernel.org/stable/c/cf24991619be317e2769310b4a367bf4a04b82bcPatch
- https://git.kernel.org/stable/c/d06d937b0a4cdb8867f04275c8100a8b943da31aPatch