# CVE-2022-49939: linux: In the Linux kernel, the following vulnerability has been resolved:  binder: fix UAF of ref->proc caused by race cond...

CVE-2022-49939 is fixed in linux on 1 platform, first by DEBIAN-CVE-2022-49939, released June 18, 2025. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2022-49939
- Priority: High
- CVSS: 7.0 (high)
- EPSS: 0.0017
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 18, 2025

## Description

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

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.19.11-1 | [DEBIAN-CVE-2022-49939](https://patchblox.com/security/data/fix/linux/debian-cve-2022-49939.md) | Jun 18, 2025 |
| Linux | linux Debian 13.5 (trixie) | 5.19.11-1 | [DEBIAN-CVE-2022-49939](https://patchblox.com/security/data/fix/linux/debian-cve-2022-49939.md) | Jun 18, 2025 |
| Linux | linux Debian 14 | 5.19.11-1 | [DEBIAN-CVE-2022-49939](https://patchblox.com/security/data/fix/linux/debian-cve-2022-49939.md) | Jun 18, 2025 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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