Bug 2492775 (CVE-2026-53150)

Summary: CVE-2026-53150 kernel: thunderbolt: Reject zero-length property entries in validator
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's Thunderbolt subsystem. The `tb_property_entry_valid()` function, which validates Thunderbolt property entries, accepts zero-length TEXT entries. This can cause an underflow in the null-termination logic, resulting in an out-of-bounds write to memory. This memory corruption could lead to a denial of service (system crash) or potentially allow for privilege escalation.
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Description OSIDB Bzimport 2026-06-25 10:05:05 UTC 
In the Linux kernel, the following vulnerability has been resolved:

thunderbolt: Reject zero-length property entries in validator

tb_property_entry_valid() accepts entries with length == 0 for
DIRECTORY, DATA, and TEXT types.  A zero-length TEXT entry passes
validation but causes an underflow in the null-termination logic:

  property->value.text[property->length * 4 - 1] = '\0';

When property->length is 0 this writes to offset -1 relative to
the allocation.

Reject zero-length entries early in the validator since they have no
valid representation in the XDomain property protocol.
Comment 1 Keith Grant 2026-06-26 00:01:09 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026062546-CVE-2026-53150-ee5c@gregkh/T