Bug 2502377 (CVE-2026-63956)

Summary: CVE-2026-63956 kernel: USB: serial: cypress_m8: fix memory corruption with small endpoint
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the Linux kernel's cypress_m8 USB serial driver. A malicious Universal Serial Bus (USB) device could report a packet size smaller than eight bytes for the interrupt-out endpoint. This can lead to memory corruption, specifically user-controlled slab corruption or a NULL-pointer dereference, potentially impacting system stability and integrity.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-07-19 16:04:47 UTC
In the Linux kernel, the following vulnerability has been resolved:

USB: serial: cypress_m8: fix memory corruption with small endpoint

Make sure that the interrupt-out endpoint max packet size is at least
eight bytes to avoid user-controlled slab corruption or NULL-pointer
dereference should a malicious device report a smaller size.