How severe is CVE-2026-74534?

No CVSS score has been assigned to CVE-2026-74534 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-74534?

CVE-2026-74534 affects the following packages: Kernel (Linux). Ecosystems affected: Linux.

How do I fix CVE-2026-74534?

Update Kernel to 6.18.44 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-74534 is resolved across your whole dependency graph.

How do I detect CVE-2026-74534 in my Linux dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Kernel. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2026-74534 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2026-74534?

O3 pinpoints whether CVE-2026-74534 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2026-74534 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-74534 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

When was CVE-2026-74534 published, and has it been updated?

CVE-2026-74534 was published on August 15, 2026 and was last updated on August 17, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐧 Linux

Not in CISA KEV

CVE-2026-74534

CVE-2026-74534 is a security vulnerability in Kernel. O3 Security confirms whether CVE-2026-74534 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Bluetooth: ISO: fix refcounting of iso_conn

Published

Aug 15, 2026

Updated

Aug 17, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Aug 17, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Real-World Exposure

1 pkg affected

🐧Kernel

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Linux packages — download data is not available via public APIs for these ecosystems.

Description

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: ISO: fix refcounting of iso_conn

iso_conn_del() and iso_chan_del() have a race that results to double-put of iso_conn:

[Task hdev->workqueue]         [Task 2]
iso_conn_del                   iso_chan_del
  iso_conn_hold_unless_zero      iso_conn_lock
  iso_conn_lock                  conn->sk = NULL
                                 iso_conn_unlock
  sk = iso_sock_hold(conn)  <---------´
  if (!sk) iso_conn_put          iso_conn_put
  iso_conn_put /* UAF */

The extra put for !sk in iso_conn_del() is currently required since failing iso_chan_add() may leave iso_conn not associated with any sk.

Fix by having iso_pi(sk)->conn own refcount when non-NULL, so iso_conn_del does not need to put it. Adjust the iso_conn_add() refcounting so that conn is put if it does not get associated with an sk.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐧Linux	`Kernel`	≥ 6.13.0&&< 6.18.44	6.18.44

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Kernel. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update Kernel to 6.18.44 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-74534 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-74534 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2026-74534. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: fix refcounting of iso_conn iso_conn_del() and iso_chan_del() have a race that results to double-put of iso_conn: [Task hdev->workqueue] [Task 2] iso_conn_del iso_chan_del iso_conn_hold_unless_zero iso_conn_lock iso_conn_lock conn->sk = NULL iso_conn_unlock sk = iso_sock_hold(conn) <---------´ if (!sk) iso_conn_put iso_conn_put iso_conn_put /* UAF */ The extra put for !sk in i

O3 Security · Impact-Aware SCA

Is CVE-2026-74534 in your dependencies?

O3 detects CVE-2026-74534 across Linux dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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