CVE-2026-89440: Linux

High severity, CVSS 7.8. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: mmc: via-sdmmc: stop card-detect handling on probe failure request_irq() registers the SD card-detect interrupt and the probe enables it before mmc_add_host() runs. If mmc_add_host() fails, the error path only unmaps the registers and returns: the interrupt stays registered, so the handler keeps running against the host once it is freed. via_sdc_isr() dereferences sdhost and its MMIO base and schedules carddet_work, which via_sdc_card_detect() also runs against freed memory through its container_of() dereference. Add a probe-error path that disables and frees the interrupt and cancels carddet_work before unmapping. carddet_work can re-enable the device interrupt via via_reset_pcictrl(), which restores PCIINTCTRL, so mask it again after cancelling the work. This issue was found by an in-house static analysis tool and confirmed by manual code review.

Affected products

• Linux Linux: from 5.10.163, before 5.10.270 (fixed in 5.10.270); from 5.15.86, before 5.15.221 (fixed in 5.15.221); from 6.1.2, before 6.1.188 (fixed in 6.1.188); from 4.9.337, before 4.10 (fixed in 4.10); from 4.14.303, before 4.15 (fixed in 4.15); from 4.19.270, before 4.20 (fixed in 4.20); …

Published 2026-09-11. Last modified 2026-09-14.