CVE-2026-53276

Published Jun 25, 2026

Last updated a month ago

CVSS high 7.8
Ubuntu

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: Fix a use-after-free of the hci_conn pointer In iso_sock_rebind_bc(), the bis pointer is cached, then the socket lock is dropped: bis = iso_pi(sk)->conn->hcon; /* Release the socket before lookups since that requires hci_dev_lock * which shall not be acquired while holding sock_lock for proper * ordering. */ release_sock(sk); hci_dev_lock(bis->hdev); During the unlocked window, could a concurrent close() destroy the connection and free the bis structure, causing hci_dev_lock(bis->hdev) to access memory after it is freed, fix this by using the hdev reference which was safely acquired via iso_conn_get_hdev().
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Secondary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-416

Social media

Hype score
Not currently trending

  1. 🚨*CVE* CVE-2026-53276 In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: Fix a use-after-free of the hci_conn pointer In iso_sock_rebind_bc(), the bis po… https://t.co/J1H7oZqEhm ----- Traducción: CVE-2026-53276 En … https://t.co/utmtNg

    @infoflowcloud

    25 Jun 2026

    34 Impressions

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Configurations

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References

Sources include official advisories and independent security research.