CVE-2022-49939
What it is
In the Linux kernel, the following vulnerability has been resolved: binder: fix UAF of ref->proc caused by race condition A transaction of type BINDER_TYPE_WEAK_HANDLE can fail to increment the reference for a node. In this case, the target proc normally releases the failed reference upon close as expected. However, if the target is dying in parallel the call will race with binder_deferred_release(), so the target could have released all of its references by now leaving the cleanup of the new failed reference unhandled. The transaction then ends and the target proc gets released making the ref->proc now a dangling pointer. Later on, ref->node is closed and we attempt to take spin_lock(&ref->proc->inner_lock), which leads to the use-after-free bug reported below. Let's fix this by cleaning up the failed reference on the spot instead of relying on the target to do so. ================================================================== BUG: KASAN: use-after-free in _raw_spin_lock+0xa8/0x150 Write of size 4 at addr ffff5ca207094238 by task kworker/1:0/590 CPU: 1 PID: 590 Comm: kworker/1:0 Not tainted 5.19.0-rc8 #10 Hardware name: linux,dummy-virt (DT) Workqueue: events binder_deferred_func Call trace: dump_backtrace.part.0+0x1d0/0x1e0 show_stack+0x18/0x70 dump_stack_lvl+0x68/0x84 print_report+0x2e4/0x61c kasan_report+0xa4/0x110 kasan_check_range+0xfc/0x1a4 __kasan_check_write+0x3c/0x50 _raw_spin_lock+0xa8/0x150 binder_deferred_func+0x5e0/0x9b0 process_one_work+0x38c/0x5f0 worker_thread+0x9c/0x694 kthread+0x188/0x190 ret_from_fork+0x10/0x20
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-362 · Race condition
- Record status
- Modified
Affected
- Linux Kernel < 4.14.293
- Linux Kernel < 4.19.258
- Linux Kernel < 5.4.213
- Linux Kernel < 5.10.142
- Linux Kernel < 5.15.66
- Linux Kernel < 5.19.8
- Linux Kernel 6.0
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2022-49939.md and follow it. Check whether this project is affected by CVE-2022-49939. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/06e5b43ca4dab06a92bf4c2f33766e6fb11b880a
- https://git.kernel.org/stable/c/229f47603dd306bc0eb1a831439adb8e48bb0eae
- https://git.kernel.org/stable/c/30d0901b307f27d36b2655fb3048cf31ee0e89c0
- https://git.kernel.org/stable/c/603a47f2ae56bf68288784d3c0a8c5b8e0a827ed
- https://git.kernel.org/stable/c/9629f2dfdb1dad294b468038ff8e161e94d0b609
- https://git.kernel.org/stable/c/a0e44c64b6061dda7e00b7c458e4523e2331b739
- https://git.kernel.org/stable/c/c2a4b5dc8fa71af73bab704d0cac42ac39767ed6
References
- https://git.kernel.org/stable/c/06e5b43ca4dab06a92bf4c2f33766e6fb11b880a
- https://git.kernel.org/stable/c/229f47603dd306bc0eb1a831439adb8e48bb0eae
- https://git.kernel.org/stable/c/30d0901b307f27d36b2655fb3048cf31ee0e89c0
- https://git.kernel.org/stable/c/603a47f2ae56bf68288784d3c0a8c5b8e0a827ed
- https://git.kernel.org/stable/c/9629f2dfdb1dad294b468038ff8e161e94d0b609
- https://git.kernel.org/stable/c/a0e44c64b6061dda7e00b7c458e4523e2331b739
- https://git.kernel.org/stable/c/c2a4b5dc8fa71af73bab704d0cac42ac39767ed6