thunderbolt: Reject oversized XDomain properties responses

Summary

In the Linux kernel, the following vulnerability has been resolved: thunderbolt: Reject oversized XDomain properties responses tb_xdp_properties_request() allocates room for 45 data dwords in its 252-byte response buffer. The XDomain length field is six bits wide, however, and a malicious peer can set it to 63. After the fixed response fields are subtracted, the driver treats this as 48 data dwords. Commit 322e93448d90 ("thunderbolt: Clamp XDomain response data copy to allocation size") only bounds the copy against data_len. If data_len is at least 48, memcpy() reads 192 bytes from the 180-byte res->data array, causing a 12-byte heap out-of-bounds read. Commit 4db2bd2ed478 ("thunderbolt: Limit XDomain response copy to actual frame size") limits the earlier copy but does not constrain this header-derived length. Reject response data lengths that exceed the allocated source buffer before copying them into the assembled property block.

Timeline

1. Oct 18, 2026, 3:45 PM UTCCVE published
2. Oct 30, 2026, 12:38 PM UTCRecord last updated

Affected versions

• Linux Linux

  Version range not reported

• Linux Linux

  4.15

• KernelLinux

  From 4.15.0 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.113; From 6.13.0 · fixed in 6.18.56; From 6.19.0 · fixed in 7.2.10

References 8