High 8.1Published Jul 19, 2026

CVE-2026-63893thunderbolt: property: Reject u32 wrap in tb_property_entry_valid()

Updated under an hour ago (Oct 28, 2026, 8:00 AM ET)

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: thunderbolt: property: Reject u32 wrap in tb_property_entry_valid() entry->value is u32 and entry->length is u16; the sum is performed in u32 and wraps. A malicious XDomain peer can pick value = 0xffffff00, length = 0x100 so the sum 0x100000000 wraps to 0 and passes the > block_len check. tb_property_parse() then passes entry->value to parse_dwdata() as a dword offset into the property block, reading attacker-directed memory far past the allocation. For TEXT-typed entries with the "deviceid" or "vendorid" keys this lands in xd->device_name / xd->vendor_name and is readable back via the per-XDomain device_name / vendor_name sysfs attributes; the leak is NUL-bounded (kstrdup() stops at the first zero byte) and untargeted (the attacker picks a delta, not an absolute address). DATA-typed entries are parsed into property->value.data but not generically surfaced to userspace. Use check_add_overflow() so a wrapped sum is rejected.

CVSS: 8.1 HIGH (v3.1, CNA)CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Weakness (CWE): CWE-190
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Analyzed
Record last updated: Oct 19, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from cdae7c07e3e3509eaabc18c1640a55dc5b99c179 before 6a63623621639acbb39bc2d9fb09559681716695; from cdae7c07e3e3509eaabc18c1640a55dc5b99c179 before e8a0b0a93a6ef958e70b1dd4930beb6dc0026b36; from cdae7c07e3e3509eaabc18c1640a55dc5b99c179 before 9fee50c4e1e42f6d3cbe30df584f9f648f626071; from cdae7c07e3e3509eaabc18c1640a55dc5b99c179 before 8d4a758b407ab3de3be86d1ceadfa35d717d30c7; from cdae7c07e3e3509eaabc18c1640a55dc5b99c179 before 5c06a3043ad944f087bb2ae0aae28d820bb9f460; from cdae7c07e3e3509eaabc18c1640a55dc5b99c179 before 31b98e503ecca8077e5247253dd5425ab84bc96d; from cdae7c07e3e3509eaabc18c1640a55dc5b99c179 before a47784aee77f33f786dc5d7375db821bdae68792; from cdae7c07e3e3509eaabc18c1640a55dc5b99c179 before 01deda0152066c6c955f0619114ea6afa070aaec	CNA record
linux linux_kernel linux:linux_kernel	from 4.15 before 5.10.259; from 5.11 before 5.15.210; from 5.16 before 6.1.176; from 6.2 before 6.6.143; from 6.7 before 6.12.93; from 6.13 before 6.18.35; from 6.19 before 7.0.12; 7.1; and 4 more ranges	NVD

References

References

https://git.kernel.org/stable/c/6a63623621639acbb39bc2d9fb09559681716695	patch
https://git.kernel.org/stable/c/e8a0b0a93a6ef958e70b1dd4930beb6dc0026b36	patch
https://git.kernel.org/stable/c/9fee50c4e1e42f6d3cbe30df584f9f648f626071	patch
https://git.kernel.org/stable/c/8d4a758b407ab3de3be86d1ceadfa35d717d30c7	patch
https://git.kernel.org/stable/c/5c06a3043ad944f087bb2ae0aae28d820bb9f460	patch
https://git.kernel.org/stable/c/31b98e503ecca8077e5247253dd5425ab84bc96d	patch
https://git.kernel.org/stable/c/a47784aee77f33f786dc5d7375db821bdae68792	patch
https://git.kernel.org/stable/c/01deda0152066c6c955f0619114ea6afa070aaec	patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.