Out-of-bounds write in Linux kernel - CVE-2026-64268
Published: July 27, 2026
Vulnerability identifier: #VU139713
CSH Severity: High
CVSS v4: 7.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-64268
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to write out of bounds.
The vulnerability exists due to an out-of-bounds write in siw_proc_rresp() in drivers/infiniband/sw/siw/siw_qp_rx.c when processing Read Response DDP segments for an outstanding RREAD over an established RDMA connection. A remote user can send Read Response segments with more total payload than requested while keeping the DDP Last flag clear to write out of bounds.
Exploitation requires a connected siw peer on an established RDMA connection over routable TCP.
Affected software
Linux kernel
How to mitigate CVE-2026-64268
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
External References
- https://git.kernel.org/stable/c/3ef7e052cbd05a8b13a51a07b185a39ec93ee1cf
- https://git.kernel.org/stable/c/423a78ff7928c2601013f73ec6d896f5597d0df5
- https://git.kernel.org/stable/c/595e6537ad1a210da32cbb9a7f91aa73090915ba
- https://git.kernel.org/stable/c/6bc89f34a4597f9f6d41f7a60c67a3153bfe8851
- https://git.kernel.org/stable/c/75c93cd3c421890f49ea93f0b978b9b7bb10e5e3
- https://git.kernel.org/stable/c/7d29f7e9dbd844cae4d3e559cf78324b9642fd6b
- https://git.kernel.org/stable/c/a31b6d18ded3cc32d9ee85a6ff0726d4274887b2
- https://git.kernel.org/stable/c/b2e26c955f8dd7e8d3f16c858db05245ea4fa817