Bug 2492785 (CVE-2026-53147)

Summary: CVE-2026-53147 kernel: thunderbolt: Validate XDomain request packet size before type cast
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's Thunderbolt component. A remote attacker could exploit this vulnerability by sending a malformed XDomain packet. This could lead to an out-of-bounds read, potentially resulting in information disclosure or system instability.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-06-25 10:05:36 UTC 
In the Linux kernel, the following vulnerability has been resolved:

thunderbolt: Validate XDomain request packet size before type cast

tb_xdp_handle_request() casts the received packet buffer to
protocol-specific structs without verifying that the allocation
is large enough for the target type.  A peer can send a minimal
XDomain packet that passes the generic header length check but is
shorter than the struct accessed after the cast, causing out-of-
bounds reads from the kmemdup allocation.

Plumb the packet length through xdomain_request_work and validate
it against the expected struct size before each cast.
Comment 1 TEJ RATHI 2026-06-26 08:04:38 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026062546-CVE-2026-53147-9761@gregkh/T