// For flags

CVE-2025-40028

binder: fix double-free in dbitmap

Severity Score

7.1
*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

In the Linux kernel, the following vulnerability has been resolved: binder: fix double-free in dbitmap A process might fail to allocate a new bitmap when trying to expand its
proc->dmap. In that case, dbitmap_grow() fails and frees the old bitmap
via dbitmap_free(). However, the driver calls dbitmap_free() again when
the same process terminates, leading to a double-free error: ================================================================== BUG: KASAN: double-free in binder_proc_dec_tmpref+0x2e0/0x55c Free of addr ffff00000b7c1420 by task kworker/9:1/209 CPU: 9 UID: 0 PID: 209 Comm: kworker/9:1 Not tainted 6.17.0-rc6-dirty #5 PREEMPT Hardware name: linux,dummy-virt (DT) Workqueue: events binder_deferred_func Call trace: kfree+0x164/0x31c binder_proc_dec_tmpref+0x2e0/0x55c binder_deferred_func+0xc24/0x1120 process_one_work+0x520/0xba4 [...] Allocated by task 448: __kmalloc_noprof+0x178/0x3c0 bitmap_zalloc+0x24/0x30 binder_open+0x14c/0xc10 [...] Freed by task 449: kfree+0x184/0x31c binder_inc_ref_for_node+0xb44/0xe44 binder_transaction+0x29b4/0x7fbc binder_thread_write+0x1708/0x442c binder_ioctl+0x1b50/0x2900 [...] ================================================================== Fix this issue by marking proc->map NULL in dbitmap_free().

In the Linux kernel, the following vulnerability has been resolved: binder: fix double-free in dbitmap A process might fail to allocate a new bitmap when trying to expand its proc->dmap. In that case, dbitmap_grow() fails and frees the old bitmap via dbitmap_free(). However, the driver calls dbitmap_free() again when the same process terminates, leading to a double-free error: ================================================================== BUG: KASAN: double-free in binder_proc_dec_tmpref+0x2e0/0x55c Free of addr ffff00000b7c1420 by task kworker/9:1/209 CPU: 9 UID: 0 PID: 209 Comm: kworker/9:1 Not tainted 6.17.0-rc6-dirty #5 PREEMPT Hardware name: linux,dummy-virt (DT) Workqueue: events binder_deferred_func Call trace: kfree+0x164/0x31c binder_proc_dec_tmpref+0x2e0/0x55c binder_deferred_func+0xc24/0x1120 process_one_work+0x520/0xba4 [...] Allocated by task 448: __kmalloc_noprof+0x178/0x3c0 bitmap_zalloc+0x24/0x30 binder_open+0x14c/0xc10 [...] Freed by task 449: kfree+0x184/0x31c binder_inc_ref_for_node+0xb44/0xe44 binder_transaction+0x29b4/0x7fbc binder_thread_write+0x1708/0x442c binder_ioctl+0x1b50/0x2900 [...] ================================================================== Fix this issue by marking proc->map NULL in dbitmap_free().

These are all security issues fixed in the kernel-devel-6.17.7-1.1 package on the GA media of openSUSE Tumbleweed.

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High
Attack Vector
Local
Attack Complexity
Low
Authentication
None
Confidentiality
Complete
Integrity
Complete
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2025-04-16 CVE Reserved
  • 2025-10-28 CVE Published
  • 2025-11-29 EPSS Updated
  • 2025-12-01 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.11 < 6.12.52
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.11 < 6.12.52"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.11 < 6.16.12
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.11 < 6.16.12"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.11 < 6.17.2
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.11 < 6.17.2"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.11 < 6.18
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.11 < 6.18"
en
Affected