Linux Distros Unpatched Vulnerability : CVE-2026-98738

critical Nessus Plugin ID 367012

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- Bluetooth: Serialize SMP remote OOB data access build_pairing_cmd() looks up remote OOB data and copies its contents without holding hdev->lock, which serializes the list's writers. After SMP finds an entry, a concurrent management Remove Remote OOB Data command can unlink and free it before SMP reads its present flag or copies its random and confirmation values. Removal can also invalidate an entry while the lookup is still traversing the list. KASAN reported: BUG: KASAN: slab-use-after-free in build_pairing_cmd+0x948/0x9b0 Call Trace: build_pairing_cmd+0x948/0x9b0 smp_recv_cb+0x459f/0x8110 l2cap_recv_frame+0xf14/0x9190 l2cap_recv_acldata+0xa64/0xd40 hci_rx_work+0x4ca/0x730 Allocated by task 87:
hci_add_remote_oob_data+0x11d/0x530 add_remote_oob_data+0x282/0x400 hci_sock_sendmsg+0x1033/0x1ea0 Freed by task 93: hci_remote_oob_data_clear+0x108/0x1c0 remove_remote_oob_data+0x198/0x220 hci_sock_sendmsg+0x1033/0x1ea0 Taking hdev->lock in build_pairing_cmd() would recurse for callers that already hold it and invert the device-to-L2CAP lock order on the receive path. Add a per-device remote_oob_lock instead, held across the SMP lookup and copies and by the add, remove and clear helpers.
Cover initialization and in-place updates as well, so SMP cannot read partially initialized or updated OOB values. Release the mutex on allocation failure, preserving the existing error return. The new critical sections acquire no device, connection or channel locks. Writers retain their existing hdev->lock protection, which continues to serialize the other readers without changing their locking or behavior.
(CVE-2026-98738)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://security-tracker.debian.org/tracker/CVE-2026-98738

Plugin Details

Severity: Critical

ID: 367012

File Name: unpatched_CVE_2026_98738.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 10/18/2026

Updated: 10/18/2026

Supported Sensors: Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.42

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2026-98738

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 9

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:U/RC:C

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:12.0, p-cpe:/a:debian:debian_linux:linux

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 10/18/2026

Reference Information

CVE: CVE-2026-98738