Description

In the Linux kernel, the following vulnerability has been resolved:

binder: fix UAF caused by offsets overwrite

Binder objects are processed and copied individually into the target
buffer during transactions. Any raw data in-between these objects is
copied as well. However, this raw data copy lacks an out-of-bounds
check. If the raw data exceeds the data section size then the copy
overwrites the offsets section. This eventually triggers an error that
attempts to unwind the processed objects. However, at this point the
offsets used to index these objects are now corrupted.

Unwinding with corrupted offsets can result in decrements of arbitrary
nodes and lead to their premature release. Other users of such nodes are
left with a dangling pointer triggering a use-after-free. This issue is
made evident by the following KASAN report (trimmed):

==================================================================
BUG: KASAN: slab-use-after-free in _raw_spin_lock+0xe4/0x19c
Write of size 4 at addr ffff47fc91598f04 by task binder-util/743

CPU: 9 UID: 0 PID: 743 Comm: binder-util Not tainted 6.11.0-rc4 #1
Hardware name: linux,dummy-virt (DT)
Call trace:
_raw_spin_lock+0xe4/0x19c
binder_free_buf+0x128/0x434
binder_thread_write+0x8a4/0x3260
binder_ioctl+0x18f0/0x258c
[...]

Allocated by task 743:
__kmalloc_cache_noprof+0x110/0x270
binder_new_node+0x50/0x700
binder_transaction+0x413c/0x6da8
binder_thread_write+0x978/0x3260
binder_ioctl+0x18f0...

Classification

CVE ID: CVE-2024-46740

CVSS Base Severity: HIGH

CVSS Base Score: 7.8

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.06% (probability of being exploited)

EPSS Percentile: 16.61% (scored less or equal to compared to others)

EPSS Date: 2025-03-19 (when was this score calculated)

References

https://git.kernel.org/stable/c/5a32bfd23022ffa7e152f273fa3fa29befb7d929
https://git.kernel.org/stable/c/3a8154bb4ab4a01390a3abf1e6afac296e037da4
https://git.kernel.org/stable/c/eef79854a04feac5b861f94d7b19cbbe79874117
https://git.kernel.org/stable/c/4f79e0b80dc69bd5eaaed70f0df1b558728b4e59
https://git.kernel.org/stable/c/1f33d9f1d9ac3f0129f8508925000900c2fe5bb0
https://git.kernel.org/stable/c/109e845c1184c9f786d41516348ba3efd9112792
https://git.kernel.org/stable/c/4df153652cc46545722879415937582028c18af5

Timeline