CVE-2026-64298

In the Linux kernel, the following vulnerability has been resolved: NFSv4: include MAY_WRITE in open permission mask for O_TRUNC POSIX requires write permission to truncate a file, so an open() that specifies O_TRUNC must be authorized for write access regardless of the O_ACCMODE access mode. nfs_open_permission_mask() builds the access mask passed to nfs_may_open(), which is the local authorization gate for OPENs the client serves itself from a cached write delegation via the can_open_delegated() path in nfs4_try_open_cached(). The mask is derived from O_ACCMODE alone, so an open(O_RDONLY | O_TRUNC) against a file the caller cannot write requests only MAY_READ and passes the local check. The OPEN is then satisfied locally and the truncation is issued to the server as a SETATTR(size=0) over the delegation stateid, which the server accepts under standard write-delegation semantics. POSIX requires that this open fail with EACCES. Include MAY_WRITE in the mask whenever O_TRUNC is set so the local check matches the access the server would have enforced.
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.2:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.2:rc2:*:*:*:*:*:*

History

12 Aug 2026, 14:54

Type Values Removed Values Added
CWE NVD-CWE-noinfo
References () https://git.kernel.org/stable/c/22c1fd1355ad4ca27aa7f0fa02719122dd92d9de - () https://git.kernel.org/stable/c/22c1fd1355ad4ca27aa7f0fa02719122dd92d9de - Patch
References () https://git.kernel.org/stable/c/30fdf4df6c3c00efec947e4ddf97f0fdd4473628 - () https://git.kernel.org/stable/c/30fdf4df6c3c00efec947e4ddf97f0fdd4473628 - Patch
References () https://git.kernel.org/stable/c/4817c8974315b666e895b7d1bb83cd3664c323b1 - () https://git.kernel.org/stable/c/4817c8974315b666e895b7d1bb83cd3664c323b1 - Patch
References () https://git.kernel.org/stable/c/5140f099ecd8a2f2808b7f7b720ee1bad8468974 - () https://git.kernel.org/stable/c/5140f099ecd8a2f2808b7f7b720ee1bad8468974 - Patch
References () https://git.kernel.org/stable/c/6bd7d0a06b53c4e797e1a9cea0d2d41aa1b26230 - () https://git.kernel.org/stable/c/6bd7d0a06b53c4e797e1a9cea0d2d41aa1b26230 - Patch
References () https://git.kernel.org/stable/c/a937e92c1d00534b5c2e3e9f4381b7e988180797 - () https://git.kernel.org/stable/c/a937e92c1d00534b5c2e3e9f4381b7e988180797 - Patch
References () https://git.kernel.org/stable/c/cb148a2762d644bff1894728e8835a9a4b84f9ea - () https://git.kernel.org/stable/c/cb148a2762d644bff1894728e8835a9a4b84f9ea - Patch
References () https://git.kernel.org/stable/c/e36501b7d4abdcd6d69a7cb901b2f286b7a3d041 - () https://git.kernel.org/stable/c/e36501b7d4abdcd6d69a7cb901b2f286b7a3d041 - Patch
First Time Linux linux Kernel
Linux
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.2:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.2:rc2:*:*:*:*:*:*

27 Jul 2026, 05:16

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 7.1

25 Jul 2026, 10:17

Type Values Removed Values Added
New CVE

Information

Published : 2026-07-25 10:17

Updated : 2026-08-12 14:54


NVD link : CVE-2026-64298

Mitre link : CVE-2026-64298

CVE.ORG link : CVE-2026-64298


JSON object : View

Products Affected

linux

  • linux_kernel