Vulnerability Note VU#38336

MIT Kerberos 5 ksu may allow either the '-r' or '-l' time-interval parameter to overflow the stack with the characters ''d', 'h', 'm', or 's'

Overview

I. Description

From the reporter:

Time-interval parsing for the "-r" and "-l" command-line options calls a library routine which uses sscanf("%d%[d]") and passes the address of an automatic int variable to correspond to the second %-sequence. But the %[ sequence needs an arbitrarily large string buffer. So it's possible to get an arbitrary-length string consisting entirely of the letter 'd' written to the stack. Other sscanf formats it tries to use will also allow a string of 'h', 'm', or 's' characters to be written, with all characters the same in any string.

II. Impact

Local user may be able to crash the machine by overwriting the stack with the characters 'd', 'h', 'm', or 's'

III. Solution

Systems Affected

No Information Available

References

Credit

This document was written by Jeff S Havrilla.

Other Information

Date Public:	2000-05-16
Date First Published:	2000-10-19
Date Last Updated:	2003-04-11
CERT Advisory:	CA-2000-06
CVE-ID(s):	CVE-2000-0392
NVD-ID(s):	CVE-2000-0392
US-CERT Technical Alerts:
Severity Metric:	0.00
Document Revision:	7

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