CVE-2024-46690
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk8th percentile - higher than 8% of all known CVEs
Summary
In the Linux kernel, in the nfsd module, there is a vulnerability in nfsd4_deleg_getattr_conflict that unsafely dereferences flc_owner without confirming that fl_lmops is the expected manager. The fix restores the behavior for the "!= &nfsd_lease_mng_ops" case as before the change, without any reference to a delegation.
Risk Assessment
The risk is a potential pointer dereference error, which could lead to system crash or unauthorized access in the NFS context.
Recommendation
It is recommended to apply the kernel patch that safely handles the presence of a third-party lease and update systems to a kernel version containing this fix.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix nfsd4_deleg_getattr_conflict in presence of third party lease It is not safe to dereference fl->c.flc_owner without first confirming fl->fl_lmops is the expected manager. nfsd4_deleg_getattr_conflict() tests fl_lmops but largely ignores the result and assumes that flc_owner is an nfs4_delegation anyway. This is wrong. With this patch we restore the "!= &nfsd_lease_mng_ops" case to behave as it did before the change mentioned below. This is the same as the current code, but without any reference to a possible delegation.