CVE-2026-89699

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 36011308b3f01ce7dc9954f3cefcbb5291af9f95affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 888dad4b557352cf85be31613407b5ba51ad07d1affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 8661d3cb38fd148947e57dbc0871fd4d3fa33bbfaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3ef5e7a01a4d74995a65496bc9166d1e980a4355affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b24843ea3de1676b29902457b38507c95a80649baffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 895a485cd3758031ef9993c0d53cf19ce8fb4cccaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 45ec115cbfecb4b3cfab7fca6f73d1b60696a25aaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 041f57056e5fb9c80adc088269322d2c61074406affected
LinuxLinux2.6.12affected
LinuxLinux0 < 2.6.12unaffected
LinuxLinux5.10.270 <= 5.10.*unaffected
LinuxLinux5.15.221 <= 5.15.*unaffected
LinuxLinux6.1.188 <= 6.1.*unaffected
LinuxLinux6.6.157 <= 6.6.*unaffected
LinuxLinux6.12.109 <= 6.12.*unaffected
LinuxLinux6.18.50 <= 6.18.*unaffected
LinuxLinux7.2.4 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References