Bluetooth: hci_conn: fix potential UAF in create_big_sync (Linux Linux)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.16 % · percentile 5 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Undergoing Analysis
Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_conn: fix potential UAF in create_big_sync Add hci_conn_valid() check in create_big_sync() to detect stale connections before proceeding with BIG creation. Handle the resulting -ECANCELED in create_big_complete() and re-validate the connection under hci_dev_lock() before dereferencing, matching the pattern used by create_le_conn_complete() and create_pa_complete(). Keep the hci_conn object alive across the async boundary by taking a reference via hci_conn_get() when queueing create_big_sync(), and dropping it in the completion callback. The refcount and the lock are complementary: the refcount keeps the object allocated, while hci_dev_lock() serializes hci_conn_hash_del()'s list_del_rcu() on hdev->conn_hash, as required by hci_conn_del(). hci_conn_put() is called outside hci_dev_unlock() so the final put (which resolves to kfree() via bt_link_release) does not run under hdev->lock, though the release path would be safe either way. Without this, create_big_complete() would unconditionally dereference the conn pointer on error, causing a use-after-free via hci_connect_cfm() and hci_conn_del().
Weaknesses (CWE)
- CWE-416 — Use After Free
References
- https://git.kernel.org/stable/c/d41093723e47255d7d74df86e2736711c1b8486e
- https://git.kernel.org/stable/c/6823f730bf195fc296d9edd09e2ca94bc1ff5584
- https://git.kernel.org/stable/c/1750a2df0eab61dc421a7afae74abdd239a44b85
- https://git.kernel.org/stable/c/dc34f8d8240f25dd137dc2758ebbcc75e3779142
- https://git.kernel.org/stable/c/f8eaf92c57ad99358dd372580d5ff87623343a72
- https://git.kernel.org/stable/c/0beddb0c380bed5f5b8e61ddbe14635bb73d0b41
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | Linux |
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | NVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary) |
European references
- ENISA EUVD · EUVD-2026-32870
- GCVE · GCVE-0-2026-46111
CERT-FR advisories
- CERTFR-2026-AVI-1252 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1229 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1163 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1162 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1066 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0956 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0954 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0927 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0926 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0864 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0833 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0807 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0782 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0731 — Multiples vulnérabilités dans les produits Microsoft · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.0 < 6.6.140cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.7 < 6.12.90cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.13 < 6.18.32cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.19 < 7.0.7cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| Linux · Linux | affected eca0ae4aea66914515e5e3098ea051b518ee5316 < d41093723e47255d7d74df86e2736711c1b8486e ; affected eca0ae4aea66914515e5e3098ea051b518ee5316 < 6823f730bf195fc296d9edd09e2ca94bc1ff5584 ; affected eca0ae4aea66914515e5e3098ea051b518ee5316 < 1750a2df0eab61dc421a7afae74abdd239a44b85 ; affected eca0ae4aea66914515e5e3098ea051b518ee5316 < dc34f8d8240f25dd137dc2758ebbcc75e3779142 ; affected eca0ae4aea66914515e5e3098ea051b518ee5316 < f8eaf92c57ad99358dd372580d5ff87623343a72 ; affected eca0ae4aea66914515e5e3098ea051b518ee5316 < 0beddb0c380bed5f5b8e61ddbe14635bb73d0b41 |
| Linux · Linux | affected 6.0 ; unaffected 0 < 6.0 ; unaffected 6.1.183 ≤ 6.1.* ; unaffected 6.6.140 ≤ 6.6.* ; unaffected 6.12.90 ≤ 6.12.* ; unaffected 6.18.32 ≤ 6.18.* |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |