CVE-2026-23184 binder: fix UAF in binder_netlink_report()
A use-after-free in the Linux kernel binder driver allows local attackers to potentially execute code or escalate privileges via netlink reporting.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-23184?
CVE-2026-23184 is a high-severity use after free vulnerability in Linux kernel, published on 14 Feb 2026. 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:
binder: fix UAF in binder_netlink_report()
Oneway transactions sent to frozen targets via binder_proc_transaction() return a BR_TRANSACTION_PENDING_FROZEN error but they are still treated as successful since the target is expected to thaw at some point. It is then not safe to access 't' after BR_TRANSACTION_PENDING_FROZEN errors as the transaction could have been consumed by the now thawed target.
This is the case for binder_netlink_report() which derreferences 't' after a pending frozen error, as pointed out by the following KASAN report:
================================================================== BUG: KASAN: slab-use-after-free in binder_netlink_report.isra.0+0x694/0x6c8 Read of size 8 at addr ffff00000f98ba38 by task binder-util/522
CPU: 4 UID: 0 PID: 522 Comm: binder-util Not tainted 6.19.0-rc6-00015-gc03e9c42ae8f #1 PREEMPT Hardware name: linux,dummy-virt (DT) Call trace: binder_netlink_report.isra.0+0x694/0x6c8 binder_transaction+0x66e4/0x79b8 binder_thread_write+0xab4/0x4440 binder_ioctl+0x1fd4/0x2940 [...]
Allocated by task 522: __kmalloc_cache_noprof+0x17c/0x50c binder_transaction+0x584/0x79b8 binder_thread_write+0xab4/0x4440 binder_ioctl+0x1fd4/0x2940 [...]
Freed by task 488: kfree+0x1d0/0x420 binder_free_transaction+0x150/0x234 binder_thread_read+0x2d08/0x3ce4 binder_ioctl+0x488/0x2940 [...] ==================================================================
Instead, make a transaction copy so the data can be safely accessed by binder_netlink_report() after a pending frozen error. While here, add a comment about not using t->buffer in binder_netlink_report().
Weakness: CWE-416
Which versions are affected by CVE-2026-23184?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-23184?
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-2026-23184 being exploited?
There is no known exploitation of CVE-2026-23184 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-23184, DEBIAN-CVE-2026-23184, GHSA-hg9w-rxwp-fw28, UBUNTU-CVE-2026-23184.