Integer overflow in Linux kernel - CVE-2026-63893
Published: July 20, 2026
Vulnerability identifier: #VU138760
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-63893
CWE-ID: CWE-190
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to an integer overflow leading to an out-of-bounds read in tb_property_entry_valid() in the thunderbolt property parser when processing a crafted XDomain property block from a peer device. A remote attacker can send crafted property entries with wrapped value and length fields to disclose sensitive information.
For TEXT-typed entries using the "deviceid" or "vendorid" keys, leaked data may be exposed through the per-XDomain sysfs device_name or vendor_name attributes. The disclosed data is NUL-bounded and the attacker controls an offset rather than an absolute address.
How to mitigate CVE-2026-63893
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/01deda0152066c6c955f0619114ea6afa070aaec
- https://git.kernel.org/stable/c/31b98e503ecca8077e5247253dd5425ab84bc96d
- https://git.kernel.org/stable/c/5c06a3043ad944f087bb2ae0aae28d820bb9f460
- https://git.kernel.org/stable/c/6a63623621639acbb39bc2d9fb09559681716695
- https://git.kernel.org/stable/c/8d4a758b407ab3de3be86d1ceadfa35d717d30c7
- https://git.kernel.org/stable/c/9fee50c4e1e42f6d3cbe30df584f9f648f626071
- https://git.kernel.org/stable/c/a47784aee77f33f786dc5d7375db821bdae68792
- https://git.kernel.org/stable/c/e8a0b0a93a6ef958e70b1dd4930beb6dc0026b36