CVE-2021-47456 can: peak_pci: peak_pci_remove(): fix UAF
A use-after-free vulnerability in the Linux kernel peak_pci driver allows attackers to cause a denial of service or potentially execute code during module removal.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-47456?
CVE-2021-47456 is a high-severity use after free vulnerability in Linux kernel, published on 22 May 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
can: peak_pci: peak_pci_remove(): fix UAF
When remove the module peek_pci, referencing 'chan' again after releasing 'dev' will cause UAF.
Fix this by releasing 'dev' later.
The following log reveals it:
[ 35.961814 ] BUG: KASAN: use-after-free in peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.963414 ] Read of size 8 at addr ffff888136998ee8 by task modprobe/5537 [ 35.965513 ] Call Trace: [ 35.965718 ] dump_stack_lvl+0xa8/0xd1 [ 35.966028 ] print_address_description+0x87/0x3b0 [ 35.966420 ] kasan_report+0x172/0x1c0 [ 35.966725 ] ? peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.967137 ] ? trace_irq_enable_rcuidle+0x10/0x170 [ 35.967529 ] ? peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.967945 ] __asan_report_load8_noabort+0x14/0x20 [ 35.968346 ] peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.968752 ] pci_device_remove+0xa9/0x250
Which versions are affected by CVE-2021-47456?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2021-47456?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2021-47456 being exploited?
There is no known exploitation of CVE-2021-47456 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2021-47456, GHSA-45hj-5gpj-93h8, UBUNTU-CVE-2021-47456.