CVE-2024-46695: In the Linux kernel, the following vulnerability has been resolved: selinux,smack: don't bypass permissions check in inode_setsecctx hook Marek Gres...

Description

In the Linux kernel, the following vulnerability has been resolved: selinux,smack: don't bypass permissions check in inode_setsecctx hook Marek Gresko reports that the root user on an NFS client is able to change the security labels on files on an NFS filesystem that is exported with root squashing enabled. The end of the kerneldoc comment for __vfs_setxattr_noperm() states: * This function requires the caller to lock the inode's i_mutex before it * is executed. It also assumes that the caller will make the appropriate * permission checks. nfsd_setattr() does do permissions checking via fh_verify() and nfsd_permission(), but those don't do all the same permissions checks that are done by security_inode_setxattr() and its related LSM hooks do. Since nfsd_setattr() is the only consumer of security_inode_setsecctx(), simplest solution appears to be to replace the call to __vfs_setxattr_noperm() with a call to __vfs_setxattr_locked(). This fixes the above issue and has the added benefit of causing nfsd to recall conflicting delegations on a file when a client tries to change its security label.

Metrics

CVSS 3.1

4.4/10

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N

EPSS Probability

0.22%

12.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-276

Affected Software

Vendor	Product	Versions	Update
Linux	Linux Kernel	< 6.6.49	—
Linux	Linux Kernel	>= 6.7, < 6.10.8	—
Linux	Linux Kernel	6.11	Rc1

References

Timeline

Published: Sep 13, 2024
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2024-46695?

In the Linux kernel, the following vulnerability has been resolved: selinux,smack: don't bypass permissions check in inode_setsecctx hook Marek Gresko reports that the root user on an NFS client is able to change the security labels on files on an NFS filesystem that is exported with root squashing enabled. The end of the kerneldoc comment for __vfs_setxattr_noperm() states: * This function requires the caller to lock the inode's i_mutex before it * is executed. It also assumes that the caller will make the appropriate * permission checks. nfsd_setattr() does do permissions checking via fh_verify() and nfsd_permission(), but those don't do all the same permissions checks that are done by security_inode_setxattr() and its related LSM hooks do. Since nfsd_setattr() is the only consumer of security_inode_setsecctx(), simplest solution appears to be to replace the call to __vfs_setxattr_noperm() with a call to __vfs_setxattr_locked(). This fixes the above issue and has the added benefit of causing nfsd to recall conflicting delegations on a file when a client tries to change its security label.

How severe is CVE-2024-46695?

CVE-2024-46695 has a CVSS score of 4.4/10 (MEDIUM severity). The EPSS model estimates a 0.22% probability of exploitation in the next 30 days.

How do I fix CVE-2024-46695?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.