![[CVE-2025-37752] Two Bytes Of Madness: Pwning The Linux Kernel With A 0x0000 Written 262636 Bytes Out-Of-Bounds](https://rdl.ink/render/https%3A%2F%2Fsyst3mfailure.io%2Ftwo-bytes-of-madness%2Fassets%2Fimages%2Ftitle.png?width=92&height=&ar=&mode=&format=avif&dpr=2)
[CVE-2025-37752] Two Bytes Of Madness: Pwning The Linux Kernel With A 0x0000 Written 262636 Bytes Out-Of-Bounds
CVE-2025-37752 is an Array-Out-Of-Bounds vulnerability in the Linux network packet scheduler, specifically in the SFQ queuing discipline. An invalid SFQ limit and a series of interactions between SFQ and the TBF Qdisc can lead to a 0x0000 being written approximately 256KB out of bounds at a misaligned offset. If properly exploited, this can enable privilege escalation. Spray sfq_slots in kmalloc-64 to prevent an immediate kernel crash when the bug is triggered. Prevent a type-confused skb from being dequeued by reconfiguring the TBF Qdisc. Drop TBF rate and add packet overhead before the OOB write occurs. Use the 0x0000 written 262636 bytes OOB to corrupt the pipe->files field of a named pipe, free the pipe, cause page-level UAF and get arbitrary R/W in that page. Reclaim the freed page with signalfd files and use the page-level R/W primitive to swap file->private_data with file->f_cred. * Get root by overwriting the process credentials with zeros via signalfd4().bounds at a misaligned offset. If properly exploited, this can enable privilege escalation.