CVE-2025-38593
HighIn the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: fix double free in 'hci_discovery_filter_clear()' Function 'hci_discovery_filter_clear()' frees 'uuids' array and then sets it to NULL. There is a tiny chance of the following race: 'hci_cmd_sync_work()' 'update_passive_scan_sync()' 'hci_update_passive_scan_sync()' 'hci_discovery_filter_clear()' kfree(uuids); <-------------------------preempted--------------------------------> 'start_service_discovery()' 'hci_discovery_filter_clear()' kfree(uuids); // DOUBLE FREE <-------------------------preempted--------------------------------> uuids = NULL; To fix it let's add locking around 'kfree()' call and NULL pointer assignment. Otherwise the following backtrace fires: [ ] ------------[ cut here ]------------ [ ] kernel BUG at mm/slub.c:547! [ ] Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP [ ] CPU: 3 UID: 0 PID: 246 Comm: bluetoothd Tainted: G O 6.12.19-kernel #1 [ ] Tainted: [O]=OOT_MODULE [ ] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ ] pc : __slab_free+0xf8/0x348 [ ] lr : __slab_free+0x48/0x348 ... [ ] Call trace: [ ] __slab_free+0xf8/0x348 [ ] kfree+0x164/0x27c [ ] start_service_discovery+0x1d0/0x2c0 [ ] hci_sock_sendmsg+0x518/0x924 [ ] __sock_sendmsg+0x54/0x60 [ ] sock_write_iter+0x98/0xf8 [ ] do_iter_readv_writev+0xe4/0x1c8 [ ] vfs_writev+0x128/0x2b0 [ ] do_writev+0xfc/0x118 [ ] __arm64_sys_writev+0x20/0x2c [ ] invoke_syscall+0x68/0xf0 [ ] el0_svc_common.constprop.0+0x40/0xe0 [ ] do_el0_svc+0x1c/0x28 [ ] el0_svc+0x30/0xd0 [ ] el0t_64_sync_handler+0x100/0x12c [ ] el0t_64_sync+0x194/0x198 [ ] Code: 8b0002e6 eb17031f 54fffbe1 d503201f (d4210000) [ ] ---[ end trace 0000000000000000 ]---
CVSS 3.1 score
7.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness type
CWE-415CVE-2025-38593 is classified as CWE-415
See CWE-415 on MITRE CWE for full details on this weakness type.
Affected versions
Linux kernel versions
5.17
and later are affected. Fixed in
6.1.159,
6.6.117,
6.12.42,
6.15.10,
6.16.1,
6.17
and their respective stable series.
References
The following references provide additional information about CVE-2025-38593 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
-
PatchKernel patch commithttps://git.kernel.org/stable/c/16852eccbdfaf41a666705e3f8be55cf2864c5ca
-
PatchKernel patch commithttps://git.kernel.org/stable/c/2935e556850e9c94d7a00adf14d3cd7fe406ac03
-
PatchKernel patch commithttps://git.kernel.org/stable/c/7ce9bb0b95fc280e9212b8922590c492ca1d9c39
Frequently asked questions
-
What is CVE-2025-38593?
CVE-2025-38593 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 . It affects Linux kernel versions from 5.17 onward and has been patched in 6.1.159, 6.6.117, 6.12.42 and others. CVE-2025-38593 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
-
What is the CVSS score for CVE-2025-38593?
CVE-2025-38593 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. -
Is there a patch available for CVE-2025-38593?
Yes — CVE-2025-38593 has been patched. Fixed versions include 6.1.159, 6.6.117, 6.12.42 and others. If you are running Linux kernel 5.17 or later up to the fix versions, apply the relevant patch for your kernel branch.
-
Is CVE-2025-38593 actively exploited?
No — CVE-2025-38593 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.