CVE-2026-46167
MediumCVSS 5.5Exploitation Probability (EPSS)
Low risk2th percentile - higher than 2% of all known CVEs
Summary
A vulnerability has been identified in the Linux kernel within the usblp driver, leading to an uninitialized heap leak via the LPGETSTATUS ioctl. The issue arises because the device's response may contain invalid data, resulting in the transmission of stale, unsafe data to the user.
Risk Assessment
Organizations may be exposed to leaks of sensitive information, potentially leading to unauthorized access to data. If exploited by a malicious device, this vulnerability could result in serious security breaches.
Recommendation
It is recommended to update the Linux kernel to the latest version where this vulnerability has been fixed. Additionally, monitoring USB devices for unauthorized or suspicious printers is advisable.
Original NVD description (English source)
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.