CVE-2025-38593Bluetooth: hci_sync: fix double free in 'hci_discovery_filter_clear()'
- 7.8HighCVSS base score
- 0.19%Exploitation in 30 daysEPSS · top 92% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In 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 ]---
Timeline
ID reserved
By Linux
- 4 months later
· 4 months later
Published
- 14 months later
· 14 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.19% · top 92% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected ad383c2c65a5baf16e334cd40a013cc302176891 – < 86f3dcd1f331cfd4fd7ec88906955134ec51afbe
- affected ad383c2c65a5baf16e334cd40a013cc302176891 – < 7ce9bb0b95fc280e9212b8922590c492ca1d9c39
- affected ad383c2c65a5baf16e334cd40a013cc302176891 – < 16852eccbdfaf41a666705e3f8be55cf2864c5ca
- affected ad383c2c65a5baf16e334cd40a013cc302176891 – < a351ff6b8ecca4229afaa0d98042bead8de64799
- affected ad383c2c65a5baf16e334cd40a013cc302176891 – < f8069f34c4c976786ded97498012225af87435d7
- affected ad383c2c65a5baf16e334cd40a013cc302176891 – < 2935e556850e9c94d7a00adf14d3cd7fe406ac03
- affected 5.17
- unaffected < 5.17
- unaffected 6.1.159 – ≤ 6.1.*
- unaffected 6.6.117 – ≤ 6.6.*
- unaffected 6.12.42 – ≤ 6.12.*
- unaffected 6.15.10 – ≤ 6.15.*
- unaffected 6.16.1 – ≤ 6.16.*
- unaffected 6.17 – ≤ *
References
References6
- https://git.kernel.org/stable/c/86f3dcd1f331cfd4fd7ec88906955134ec51afbe (opens in a new tab)
- https://git.kernel.org/stable/c/7ce9bb0b95fc280e9212b8922590c492ca1d9c39 (opens in a new tab)
- https://git.kernel.org/stable/c/16852eccbdfaf41a666705e3f8be55cf2864c5ca (opens in a new tab)
- https://git.kernel.org/stable/c/a351ff6b8ecca4229afaa0d98042bead8de64799 (opens in a new tab)
- https://git.kernel.org/stable/c/f8069f34c4c976786ded97498012225af87435d7 (opens in a new tab)
- https://git.kernel.org/stable/c/2935e556850e9c94d7a00adf14d3cd7fe406ac03 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-27922 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-38593)Record last updated .