Product Affected

All versions of JUNOS software released prior to February 9, 2002.
Low

Problem

A security-related vulnerability was recently discovered in the JUNOS software. This vulnerability is described in detail in the FreeBSD Security Advisory FreeBSD-SA-02:09.fstatfs and in PR/21769. A user logged in to a Juniper Networks router could panic the JUNOS kernel by calling the fstatfs() system call using an invalid file descriptor. (The descriptor becomes invalid because the file is deleted.) Only file descriptors that refer to files in a procfs file system are known to exploit this race condition.

Solution

The fstatfs() system call was updated to remove the race condition.

The fix is included in all versions of JUNOS software released on or after February 10, 2002.

Severity Assessment

There is minimal risk associated with this vulnerability. To exploit it, a user would have to be logged in to a Juniper Networks router and invoke the fstatfs() system call using a file descriptor referring to a file deleted from a procfs file system. You cannot invoke the fstatfs() system call in this manner from the JUNOS command-line interface (CLI).

This vulnerability cannot be exploited remotely