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.

A flaw was found in the Linux kernel's Server Message Block (SMB) client. A remote attacker could exploit a vulnerability where the client improperly handles SMB2 responses containing overlapping data areas. This incorrect processing of malformed network data could lead to a denial of service (DoS) or other severe system impact, compromising the availability and potentially the confidentiality of the affected system.

Red Hat Enterprise Linux 10 Not affected kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Not affected kernel Red Hat Enterprise Linux 9 Not affected kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-64257 https://nvd.nist.gov/vuln/detail/CVE-2026-64257 https://lore.kernel.org/linux-cve-announce/2026072556-CVE-2026-64257-cdc9@gregkh/T