CVE-2026-31544: firmware: arm_scmi: Fix NULL dereference on notify error path

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-04-24 · updated 2026-06-17
Weakness: CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: firmware: arm_scmi: Fix NULL dereference on notify error path Since commit b5daf93b809d1 ("firmware: arm_scmi: Avoid notifier registration for unsupported events") the call chains leading to the helper __scmi_event_handler_get_ops expect an ERR_PTR to be returned on failure to get an handler for the requested event key, while the current helper can still return a NULL when no handler could be found or created. Fix by forcing an ERR_PTR return value when the handler reference is NULL.

Affected products

Linux kernel: from 6.17 before 6.18.20; from 6.19 before 6.19.10; 7.0-rc1, 7.0-rc2, 7.0-rc3, 7.0-rc4, 7.0-rc5 — fixed in 6.18.20, 6.19.10

How to fix

Upgrade to a fixed version: Linux kernel 6.18.20, 6.19.10. Check the vendor advisory for mitigations.

References

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