CVE-2025-22027 is a race condition vulnerability in the Linux kernel's media subsystem, specifically within the streamzap driver that handles certain USB remote control devices. The flaw arises from an incorrect sequence of operations during device disconnection. In the vulnerable code, the function streamzap_disconnect() calls rc_unregister_device() before usb_kill_urb(). The rc_unregister_device() function frees and nullifies the dev->raw pointer, which is subsequently accessed by the usb_kill_urb() function that waits for ongoing USB requests to complete. This leads to a use-after-free condition and a NULL pointer dereference in the ir_raw_event_store_with_filter() function, which processes raw infrared events. The race condition occurs because the dev->raw pointer is checked for NULL but can become invalid between the check and its use due to concurrent execution of the disconnect and callback handlers. This vulnerability was discovered by the Linux Verification Center using the Syzkaller fuzzing tool and has been addressed by reordering the calls so that usb_kill_urb() is invoked before rc_unregister_device(), ensuring that all USB requests are properly terminated before resources are freed. No known exploits are reported in the wild yet, and the vulnerability affects specific Linux kernel versions identified by commit hashes. The issue impacts kernel stability and could lead to system crashes or denial of service if exploited.

For European organizations, this vulnerability poses a risk primarily to systems running affected Linux kernel versions with the streamzap driver enabled, which is common in environments using USB infrared remote controls or similar media devices. Exploitation could cause kernel crashes leading to denial of service, impacting availability of critical systems such as servers, embedded devices, or workstations. While the vulnerability does not directly enable privilege escalation or data leakage, the resulting instability could disrupt business operations, especially in sectors relying on Linux-based infrastructure like telecommunications, manufacturing, and public services. Additionally, if attackers combine this flaw with other vulnerabilities, it could facilitate more severe attacks. The lack of known exploits currently reduces immediate risk, but the widespread use of Linux in Europe means that unpatched systems remain vulnerable to potential future exploitation.

European organizations should promptly apply the official Linux kernel patches that reorder the disconnect sequence to call usb_kill_urb() before rc_unregister_device(). System administrators must verify that their Linux distributions have incorporated this fix, especially in kernels used in production environments. For systems where immediate patching is not feasible, disabling or unloading the streamzap driver can mitigate exposure, provided that the functionality it supports is not critical. Additionally, organizations should implement kernel crash monitoring and logging to detect potential exploitation attempts. Employing strict access controls to limit user ability to interact with USB devices and enforcing policies on device usage can reduce attack surface. Regularly updating kernel versions and subscribing to Linux security advisories will ensure timely awareness of related vulnerabilities. Finally, integrating fuzz testing tools like Syzkaller in development and QA processes can help identify similar race conditions proactively.