CVE-2026-74733: gpio: pca953x: fix pca953x_irq_bus_sync_unlock regmap lock

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-22 · updated 2026-10-30

Description

In the Linux kernel, the following vulnerability has been resolved: gpio: pca953x: fix pca953x_irq_bus_sync_unlock regmap lock Locking is disabled in the regmap config as this driver uses its own lock. This means that all calls to regmap functions (read or write) must hold the i2c_lock. The function pca953x_irq_bus_sync_unlock() did not do this, and it was therefore possible that multiple threads could cause an incorrect register to be read/written. A previous patch partly fixed this, but only protected the write to the interrupt mask register, and not the read from the direction register.

Affected products

Linux: from 6.1.101 before 6.1.191; from 6.6.42 before 6.6.160; from 6.9.11 before 6.10 — fixed in 6.1.191, 6.6.160, 6.10

How to fix

Upgrade to a fixed version: Linux 6.1.191, 6.6.160, 6.10. Check the vendor advisory for mitigations.

References

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