nfsd in the Linux kernel before 2.6.28.9 does not drop the CAP_MKNOD capability before handling a user request in a thread, which allows local users to create device nodes, as demonstrated on a filesystem that has been exported with the root_squash option.
git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commitdiff%3Bh=76a67ec6fb79ff3570dcb5342142c16098299911
lists.opensuse.org/opensuse-security-announce/2009-04/msg00007.html
lists.opensuse.org/opensuse-security-announce/2009-05/msg00002.html
lists.opensuse.org/opensuse-security-announce/2009-06/msg00000.html
lists.opensuse.org/opensuse-security-announce/2009-06/msg00001.html
secunia.com/advisories/34422
secunia.com/advisories/34432
secunia.com/advisories/34786
secunia.com/advisories/35121
secunia.com/advisories/35185
secunia.com/advisories/35343
secunia.com/advisories/35390
secunia.com/advisories/35394
secunia.com/advisories/35656
secunia.com/advisories/37471
thread.gmane.org/gmane.linux.kernel/805280
www.debian.org/security/2009/dsa-1800
www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.28.9
www.openwall.com/lists/oss-security/2009/03/23/1
www.redhat.com/support/errata/RHSA-2009-1081.html
www.securityfocus.com/archive/1/507985/100/0/threaded
www.securityfocus.com/bid/34205
www.ubuntu.com/usn/usn-793-1
www.vmware.com/security/advisories/VMSA-2009-0016.html
www.vupen.com/english/advisories/2009/0802
www.vupen.com/english/advisories/2009/3316
exchange.xforce.ibmcloud.com/vulnerabilities/49356
oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10314
oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A8382