Kernel-level vulnerability in the Linux Bluetooth stack affects many Linux distributions and devices; can enable kernel compromise or outages across enterprise systems.
CVE-2026-74534
Use-after-free in Linux Bluetooth ISO refcounting may allow kernel compromise.
Is CVE-2026-74534 being exploited?
Not confirmed. CVE-2026-74534 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.24% probability of exploitation in the next 30 days.
How severe is CVE-2026-74534?
CVE-2026-74534 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-74534?
Yes. A fix has been recorded for CVE-2026-74534. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-74534 affect?
CVE-2026-74534 affects Linux kernel (Bluetooth ISO subsystem), Linux distributions with affected kernels (Ubuntu, Debian, RHEL, etc.), Android devices using affected kernels, Embedded/IoT devices with Bluetooth (BlueZ). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-74534?
Apply vendor kernel updates ASAP; disable/restrict Bluetooth until patched.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Nearby attacker via Bluetooth ISO can trigger a use-after-free, causing kernel crashes or potential kernel-level code execution.
Immediate action required
- affected>= dc26097bdb864a0d5955b9a25e43376ffc1af99b and < 3b921533e8aa95b77aadcf31737595578e735f3c
- affected>= dc26097bdb864a0d5955b9a25e43376ffc1af99b and < 8208b4939afb0a1977fffe902c3ca42fe0f3baaa
- affected>= dc26097bdb864a0d5955b9a25e43376ffc1af99b and < fdfde532ab1caa165fcd8985001157ac8b4db365
- affectedf53e7489273dc2bb307bf50f319b3762d45534f0
- affecteda58d0f5dac322e16cc75334d000666512341bde5
- affected>= 6.11.11 and < 6.12
- affected>= 6.12.2 and < 6.13
- affected6.13
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.