CVE-2026-68434: serial: 8250_mid: Fix NULL function pointer dereference on DNV/ICX-D/SNR platforms

Severity: unknown
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: 2026-08-12 · updated 2026-08-23

Description

In the Linux kernel, the following vulnerability has been resolved: serial: 8250_mid: Fix NULL function pointer dereference on DNV/ICX-D/SNR platforms Commit b1b4efea05a5 ("serial: 8250_mid: Disable DMA for selected platforms") replaced the dnv_board setup and exit callbacks with PTR_IF(false, ...), which evaluates to NULL. However, the three call sites in mid8250_probe() and mid8250_remove() unconditionally dereference these function pointers without NULL checks, causing a NULL pointer dereference (kernel oops) on any Denverton (DNV), Ice Lake Xeon D (ICX-D/CDF), or Snowridge (SNR) platform. Fix this by adding the missing NULL checks before calling the setup and exit callbacks.

Affected products

Linux kernel: from 5.10.261 before 5.10.266; from 5.15.212 before 5.15.217; from 6.1.178 before 6.1.183; from 6.6.145 before 6.6.148; from 6.12.96 before 6.12.101; from 6.18.39 before 6.18.42 — fixed in 5.10.266, 5.15.217, 6.1.183, 6.12.101, 6.18.42, 6.6.148

How to fix

Upgrade to a fixed version: Linux kernel 5.10.266, 5.15.217, 6.1.183, 6.12.101. Check the vendor advisory for mitigations.

References

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