CVE-2026-63893

Status: UPDATED  |  Advisory ID: CVE-2026-63893

Key Details

Affected Products, Subsystems & Sectors

What to Know

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. (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References