CVE-2026-64257 — smb: client: reject overlapping data areas in SMB2 responses
In the Linux kernel, the following vulnerability has been resolved: smb: client: reject overlapping data areas in SMB2 responses Commit 53b7c271f06b ("smb: client: restrict im…
Published: 2026-07-25 · CVSS: 9.1 · CVSS 3.1
In the Linux kernel, the following vulnerability has been resolved: smb: client: reject overlapping data areas in SMB2 responses Commit 53b7c271f06b ("smb: client: restrict implied bcc[0] exemption to responses without data area") restricted the implied bcc[0] length exception to responses without a data area. However, the overlap handling in __smb2_calc_size() clears data_length, which can make an invalid response appear to have no data area and so qualify for the exception. Track data area overlap separately and reject such responses before applying the length compatibility exceptions.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7