7.8
HIGH CVSS 3.1
CVE-2026-63945
Bluetooth: ISO: serialize iso_sock_clear_timer with socket lock
Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: serialize iso_sock_clear_timer with socket lock iso_sock_close() calls iso_sock_clear_timer() before acquiring lock_sock(sk). iso_sock_clear_timer() reads iso_pi(sk)->conn twice without the socket lock held: if (!iso_pi(sk)->conn) return; cancel_delayed_work(&iso_pi(sk)->conn->timeout_work); Concurrently, iso_conn_del() executes under lock_sock(sk) and calls iso_chan_del(), which sets iso_pi(sk)->conn to NULL and may result in the final reference to the connection being dropped: CPU0 CPU1 ---- ---- iso_sock_clear_timer() if (conn != NULL) ... lock_sock(sk) iso_chan_del() iso_pi(sk)->conn = NULL cancel_delayed_work(conn) /* NULL deref or UAF */ iso_pi(sk)->conn is not stable across the unlock window, causing a NULL pointer dereference or use-after-free. Serialize iso_sock_clear_timer() with the socket lock by moving it inside lock_sock()/release_sock(), matching the pattern used in iso_conn_del() and all other call sites.

INFO

Published Date :

July 19, 2026, 4:17 p.m.

Last Modified :

July 27, 2026, 5:44 p.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2026-63945 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
Serialize timer clearing with socket lock to prevent race conditions.
  • Move iso_sock_clear_timer inside lock_sock/release_sock.
  • Acquire socket lock before accessing connection data.
  • Ensure stable access to connection information.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-63945 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-63945 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-63945 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-63945 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jul. 20, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jul. 19, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'ccf74f2390d60a2f9a75ef496d2564abb478f46a', 'lessThan': 'd9cbf7144ec589a3f0cc91f74a1a1af2d2b14afa', 'versionType': 'git'}, {'status': 'affected', 'version': 'ccf74f2390d60a2f9a75ef496d2564abb478f46a', 'lessThan': '35f68f36d9883d56dec21cf85f7556d4657fc393', 'versionType': 'git'}, {'status': 'affected', 'version': 'ccf74f2390d60a2f9a75ef496d2564abb478f46a', 'lessThan': '996c2104d0726a8fe584f85b3d6327197374a348', 'versionType': 'git'}, {'status': 'affected', 'version': 'ccf74f2390d60a2f9a75ef496d2564abb478f46a', 'lessThan': 'bc08c15746f25f41dd0508b25780d1e84acbb2ef', 'versionType': 'git'}, {'status': 'affected', 'version': 'ccf74f2390d60a2f9a75ef496d2564abb478f46a', 'lessThan': '51cb9dcfdf9a1bccf312ab2ae4b62db629f7dcd5', 'versionType': 'git'}, {'status': 'affected', 'version': 'ccf74f2390d60a2f9a75ef496d2564abb478f46a', 'lessThan': '4b5f8e608749b7e8fa386c6e4301cf9272595859', 'versionType': 'git'}], 'programFiles': ['net/bluetooth/iso.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.0'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.0', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.1.176', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.143', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.93', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.35', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.12', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/bluetooth/iso.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: serialize iso_sock_clear_timer with socket lock iso_sock_close() calls iso_sock_clear_timer() before acquiring lock_sock(sk). iso_sock_clear_timer() reads iso_pi(sk)->conn twice without the socket lock held: if (!iso_pi(sk)->conn) return; cancel_delayed_work(&iso_pi(sk)->conn->timeout_work); Concurrently, iso_conn_del() executes under lock_sock(sk) and calls iso_chan_del(), which sets iso_pi(sk)->conn to NULL and may result in the final reference to the connection being dropped: CPU0 CPU1 ---- ---- iso_sock_clear_timer() if (conn != NULL) ... lock_sock(sk) iso_chan_del() iso_pi(sk)->conn = NULL cancel_delayed_work(conn) /* NULL deref or UAF */ iso_pi(sk)->conn is not stable across the unlock window, causing a NULL pointer dereference or use-after-free. Serialize iso_sock_clear_timer() with the socket lock by moving it inside lock_sock()/release_sock(), matching the pattern used in iso_conn_del() and all other call sites.
    Added Reference https://git.kernel.org/stable/c/35f68f36d9883d56dec21cf85f7556d4657fc393
    Added Reference https://git.kernel.org/stable/c/4b5f8e608749b7e8fa386c6e4301cf9272595859
    Added Reference https://git.kernel.org/stable/c/51cb9dcfdf9a1bccf312ab2ae4b62db629f7dcd5
    Added Reference https://git.kernel.org/stable/c/996c2104d0726a8fe584f85b3d6327197374a348
    Added Reference https://git.kernel.org/stable/c/bc08c15746f25f41dd0508b25780d1e84acbb2ef
    Added Reference https://git.kernel.org/stable/c/d9cbf7144ec589a3f0cc91f74a1a1af2d2b14afa
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.