CVE-2026-46186
Bluetooth: virtio_bt: validate rx pkt_type header length
At a glance
- Source
- NVD
- EPSS
- EPSS 0.12 % · percentile 2 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Analyzed
Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: virtio_bt: validate rx pkt_type header length virtbt_rx_handle() reads the leading pkt_type byte from the RX skb and forwards the remainder to hci_recv_frame() for every event/ACL/SCO/ISO type, without checking that the remaining payload is at least the fixed HCI header for that type. After the preceding patch bounds the backend-supplied used.len to [1, VIRTBT_RX_BUF_SIZE], a one-byte completion still reaches hci_recv_frame() with skb->len already pulled to 0. If the byte happened to be HCI_ACLDATA_PKT, the ACL-vs-ISO classification fast-path in hci_dev_classify_pkt_type() dereferences hci_acl_hdr(skb)->handle whenever the HCI device has an active CIS_LINK, BIS_LINK, or PA_LINK connection, reading two bytes of uninitialized RX-buffer data. The same hazard exists for every packet type the driver accepts because none of the switch cases in virtbt_rx_handle() check skb->len against the per-type minimum HCI header size before handing the frame to the core. After stripping pkt_type, require skb->len to cover the fixed header size for the selected type (event 2, ACL 4, SCO 3, ISO 4) before calling hci_recv_frame(); drop ratelimited otherwise. Unknown pkt_type values still take the original kfree_skb() default path. Use bt_dev_err_ratelimited() because both the length and pkt_type values come from an untrusted backend that can otherwise flood the kernel log.
Weaknesses (CWE)
- CWE-908 — Use of Uninitialized Resource
References
- https://git.kernel.org/stable/c/149cfb42ad69c7964fd9f2c43831da9152007129
- https://git.kernel.org/stable/c/7b2d4c04816cdc887f472caaf7fc966cfc107e40
- https://git.kernel.org/stable/c/1e1e509b6fd2a42421745bbcd98bd16daad20904
- https://git.kernel.org/stable/c/2c1143564c71e7497b42d8360a8379ccbb011d3c
- https://git.kernel.org/stable/c/3485c7236c59c8c34a41af1c4b52982437554e79
- https://git.kernel.org/stable/c/f743eab6486965f276c7e3f1700895f014fdc6db
- https://git.kernel.org/stable/c/daf23014e5d975e72ea9c02b5160d3fcf070ea47
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H | NVD · nvd@nist.gov (Primary) |
European references
- ENISA EUVD · EUVD-2026-32813
- GCVE · GCVE-0-2026-46186
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-1162 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1093 — 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-1064 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0985 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · 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-0862 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · 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:*:*:*:*:*:*:*:*≥ 5.15.78 < 5.15.209cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.0.8 < 6.1cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.1.1 < 6.1.175cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.2 < 6.6.140cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.7 < 6.12.88cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.13 < 6.18.30cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.19 < 7.0.7cpe:2.3:o:linux:linux_kernel:6.1:-:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.1:rc4:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.1:rc5:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.1:rc6:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.1:rc7:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.1:rc8:*:*:*:*:*:*cpe: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 cf2719a21fdb9d4c8e9c834d279163609bef575d < 149cfb42ad69c7964fd9f2c43831da9152007129 ; affected 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be < 7b2d4c04816cdc887f472caaf7fc966cfc107e40 ; affected 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be < 1e1e509b6fd2a42421745bbcd98bd16daad20904 ; affected 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be < 2c1143564c71e7497b42d8360a8379ccbb011d3c ; affected 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be < 3485c7236c59c8c34a41af1c4b52982437554e79 ; affected 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be < f743eab6486965f276c7e3f1700895f014fdc6db |
| Linux · Linux | affected 6.1 ; unaffected 0 < 6.1 ; unaffected 5.15.209 ≤ 5.15.* ; unaffected 6.1.175 ≤ 6.1.* ; unaffected 6.6.140 ≤ 6.6.* ; unaffected 6.12.88 ≤ 6.12.* |
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 |