CVE-2026-74537
HIGHCVE-2026-74537 is a high-severity (CVSS 8.8) vulnerability in Kernel. O3 Security confirms whether CVE-2026-74537 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Bluetooth: ISO: hold sk properly in iso_conn_ready
Real-World Exposure
KernelReal-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: hold sk properly in iso_conn_ready
sk deref in iso_conn_ready must be done either under conn->lock, or holding a refcount, to avoid concurrent close. conn->sk is currently accessed without either:
[Task 1] [Task 2]
iso_sock_release
iso_conn_ready
sk = conn->sk
lock_sock(sk)
conn->sk = NULL
lock_sock(sk)
release_sock(sk)
iso_sock_kill(sk)
UAF on sk deref
Fix possible UAF by holding sk refcount in iso_conn_ready(). Also recheck after lock_sock that the socket is still valid. Adjust locking so conn->sk is cleared only under lock_sock.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐧Linux | Kernel | ≥ 5.15.0&&< 6.18.44 | 6.18.44 |
Detection & mitigation playbook
Open-source dependencyDetect
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-2026-74537 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-2026-74537 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-2026-74537. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-74537 in your dependencies?
O3 detects CVE-2026-74537 across Linux dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.