rtl8723bs driver CVE-2025-68256

In the Linux kernel, the following vulnerability has been resolved:

staging: rtl8723bs: fix out-of-bounds read in rtw_get_ie() parser

The Information Element (IE) parser rtw_get_ie() trusted the length byte of each IE without validating that the IE body (len bytes after the 2-byte header) fits inside the remaining frame buffer. A malformed frame can advertise an IE length larger than the available data, causing the parser to increment its pointer beyond the buffer end. This results in out-of-bounds reads or, depending on the pattern, an infinite loop.

Fix by validating that (offset + 2 + len) does not exceed the limit before accepting the IE or advancing to the next element.

This prevents OOB reads and ensures the parser terminates safely on malformed frames.

The vulnerability affects the rtl8723bs staging Wi-Fi driver within the Linux kernel; exact affected kernel version ranges are not enumerated in the provided data (no CPE strings supplied), but the seven git.kernel.org stable commit references (e.g. 154828bf9559, 30c558447e90, 9829c6e1b2e4, a54e2b2db1b7, b977eb318028, c0d93d69e147, df191dd9f4c7) indicate the fix was backported across multiple stable branches, implying a broad range of prior kernels are affected. Distribution exposure is confirmed for Ubuntu via advisories USN-8185-1, USN-8179-2, and USN-8184-1 (https://ubuntu.com/security/notices/USN-8185-1, https://ubuntu.com/security/notices/USN-8179-2, https://ubuntu.com/security/notices/USN-8184-1). Only systems that possess RTL8723BS Wi-Fi hardware and load this driver are practically exposed.