CVE-2026-74340
OOB heap read in Linux wcn36xx Wi‑Fi driver via unvalidated firmware 'count' field.
Is CVE-2026-74340 being exploited?
Not confirmed. CVE-2026-74340 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 0.27% probability of exploitation in the next 30 days.
How severe is CVE-2026-74340?
CVE-2026-74340 is rated High with a CVSS score of 8.1. 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-2026-74340?
Yes. A fix has been recorded for CVE-2026-74340. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-74340 affect?
CVE-2026-74340 affects Linux kernel (wcn36xx driver), Devices using Qualcomm WCN36xx Wi‑Fi firmware, Android devices with WCN36xx, Embedded/Linux IoT devices with WCN36xx. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-74340?
Update kernel and vendor Wi‑Fi firmware to the patched releases immediately.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Firmware-controlled count can trigger out-of-bounds heap reads causing kernel info disclosure and crashes; may enable privilege escalation when chained.
Patch when possible
- affected>= 43efa3c0f241e04862be8e6a68ff765d36cde1ba and < 22b0b8572a64362531dd0ed499b75e16282aeb2b
- affected>= 43efa3c0f241e04862be8e6a68ff765d36cde1ba and < 3cf92b44c4fb88a5e8de8733a4494c0956606bca
- affected>= 43efa3c0f241e04862be8e6a68ff765d36cde1ba and < 0907c06dccae9e3c8d5a68eb9014beec73a36e79
- affected>= 43efa3c0f241e04862be8e6a68ff765d36cde1ba and < 64228dfc4247aca178c01e5a37af7d8dcc7a6089
- affected>= 43efa3c0f241e04862be8e6a68ff765d36cde1ba and < 23d210877968657bd07e1a517e0b516db20a1d80
- affected>= 43efa3c0f241e04862be8e6a68ff765d36cde1ba and < f03782f7f41f2afee5076a1ef08ced5649218771
- affected>= 43efa3c0f241e04862be8e6a68ff765d36cde1ba and < f987efff29a5fe45320ea5991c9d5cb98b676953
- affected>= 43efa3c0f241e04862be8e6a68ff765d36cde1ba and < df2187acfca6c6cca372c5d35f42394d9c270b09
- affected4.11
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.