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CVE intelligence

CVE-2026-74738

Vulnerability intelligence

Published Aug 26, 2026Sources checked Nov 3, 2026
N/ACVSS not listedScore unavailable
What this means

Review the available evidence

CVE-2026-74738. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

CISA KEVNot listedBased on the latest collected catalog
EPSS0.2%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview

What is CVE-2026-74738?

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

regmap: sdw-mbq: don't call an unset readable_reg callback

regmap_sdw_mbq_poll_busy() decides whether to poll the Function Busy bit by calling ctx->readable_reg(), which is a straight copy of config->readable_reg. That callback is optional: regmap_readable() treats a NULL ->readable_reg as "every register is readable", and drivers rely on that. es9356 and tac5xx2-sdw both build an MBQ regmap without one.

Since commit ca1b11b36d82 ("regmap: sdw-mbq: Allow defers on undeferrable controls") the poll runs on every -ENODATA, not only for Controls the driver marked deferrable, so any of those devices answering COMMAND_IGNORED takes the kernel through a NULL function pointer.

Treat a missing callback the way the rest of regmap does and poll.

Source: NVD