In the Linux kernel, the following vulnerability has been resolved:
nfsd: validate symlink target length in NFSv4 CREATE
nfsd4_decode_create() accepts an unbounded cr_datalen from the wire for
NF4LNK symlink targets, allowing a client to force a kmalloc of up to
the maximum RPC payload size (several MiB) per COMPOUND op that persists
until compound teardown. The VFS rejects oversized targets with
ENAMETOOLONG, but the allocation has already occurred.
Reject cr_datalen == 0 early with nfserr_inval and cr_datalen greater
than NFS4_MAXPATHLEN (PATH_MAX) with nfserr_nametoolong to bound the
allocation.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v3.1
References 8
https://git.kernel.org/stable/c/041f57056e5fb9c80adc088269322d2c61074406
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/45ec115cbfecb4b3cfab7fca6f73d1b60696a25a
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/895a485cd3758031ef9993c0d53cf19ce8fb4ccc
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/b24843ea3de1676b29902457b38507c95a80649b
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/36011308b3f01ce7dc9954f3cefcbb5291af9f95
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/3ef5e7a01a4d74995a65496bc9166d1e980a4355
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/8661d3cb38fd148947e57dbc0871fd4d3fa33bbf
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/888dad4b557352cf85be31613407b5ba51ad07d1
416baaa9-dc9f-4396-8d5f-8c081fb06d67