Bug 2451195 (CVE-2026-23307)

Summary: CVE-2026-23307 kernel: can: ems_usb: ems_usb_read_bulk_callback(): check the proper length of a message
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: medium    
Version: unspecifiedKeywords: Security
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OS: Linux   
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A flaw was found in the Linux kernel's ems_usb module. This vulnerability occurs because the system does not properly verify the length of messages it receives. An attacker could exploit this weakness by sending specially crafted messages, potentially causing the system to crash (Denial of Service) or, in some cases, execute unauthorized code.
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Description OSIDB Bzimport 2026-03-25 11:04:01 UTC 
In the Linux kernel, the following vulnerability has been resolved:

can: ems_usb: ems_usb_read_bulk_callback(): check the proper length of a message

When looking at the data in a USB urb, the actual_length is the size of
the buffer passed to the driver, not the transfer_buffer_length which is
set by the driver as the max size of the buffer.

When parsing the messages in ems_usb_read_bulk_callback() properly check
the size both at the beginning of parsing the message to make sure it is
big enough for the expected structure, and at the end of the message to
make sure we don't overflow past the end of the buffer for the next
message.
Comment 1 Alexander B 2026-03-25 16:51:47 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026032528-CVE-2026-23307-60f2@gregkh/T