CVE-2026-68339: Bluetooth: btusb: validate Realtek vendor event length

mediumCVSS 5.5CVE-2026-68339

CSIRTS triage

vendor: Linux product: Linux kernel Memory corruption

What: The Bluetooth USB driver fails to validate the length of Realtek vendor events, permitting out-of-bounds read or write.
Who is affected: Linux systems with Bluetooth adapters using the Realtek vendor implementation.
Urgency: Medium priority; CVSS 5.5 Bluetooth vulnerability warrants timely patching but not immediately critical.
Action: Update to a patched Linux kernel version containing the fix for CVE-2026-68339.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 5.5
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-68339

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-683390.21% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 11% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-68339	coverage & exploitation status	NVD · CVE.org

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