The nfsaddmntent function in support/nfs/nfsmntent.c in the mount.nsf tool in nfs-utils before 1.2.4 attempts to append to the /etc/mtab file without first checking whether resource limits would interfere, which allows local users to corrupt this file via a process with a small RLIMIT_FSIZE value, a related issue to CVE-2011-1089.