CVE-2026-63893

Sažetak

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.

Reference

CVSS

Base:	8.1
Impact:	5.2
Exploitability:	2.8

Pristup

Vektor	Složenost	Autentikacija
ADJACENT_NETWORK	LOW	NONE

Impact

Povjerljivost	Cjelovitost	Dostupnost
HIGH	NONE	HIGH

CVSS vektor

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Zadnje važnije ažuriranje

20-07-2026 - 15:16

Objavljeno

19-07-2026 - 16:17