Re: PST Linux Advisor--------Dsh-0.24.0 in debian has a home env Buffer Overflow Vulnerability

From: Vade 79 <v9_at_fakehalo.deadpig.org>
Date: 14 Aug 2003 19:05:19 -0000

('binary' encoding is not supported, stored as-is) In-Reply-To: <20030810011227.5888.qmail_at_www.securityfocus.com>

> ssize_t buflen = 50 * strlen(fmt); /* pick a number, any number
>*/.............lol
> *strp = malloc(buflen);
>
> if (*strp)
> {
> va_list ap;
> va_start(ap, fmt);
> vsnprintf(*strp, buflen, fmt,
ap);..................................lol

>getenv("HOME") >50*strlen(%s/.dsh/dsh.conf) ......buf overflow......

how do you figure? it uses the same buflen value to limit the amount
written to the buffer in the vsnprintf call as it was allocated(cept
didn't add space for the null byte)? am i missing something?
Received on Aug 14 2003